Do aerobic and anaerobic capacities affect the ability to repeatedly escape from predators, and how does personality play a role?

Abstract

The escape response is the main anti-predator strategy used by fish to escape from predators. It consists of a rapid muscular contraction that quickly thrusts the fish in a direction opposite to that of the predator. Although, this swimming performance involves primarily the activation of white anaerobic muscles, recent evidence suggests that the capacity to aerobically repay an O2 debt, due to anaerobic activity, can affect the escape response. This link between escape response and aerobic and anaerobic capacity might be especially relevant in the context of escape from multiple predator attacks, i.e. when predators attack in groups. However, this hypothesis has never been tested before. Therefore, this project aims to investigate the relationship between the ability to repeatedly escape from predators and the aerobic scope (AS) and Excess Post-exercise Oxygen Consumption (EPOC). Our results showed that across repeated escape response stimulations, the responsiveness to predator attack simulation declined, probably due to habituation rather than metabolic fatigue, while escape latency remained stable. However, these two variables were not associated with AS or EPOC. While in this report, we only focus on the link between metabolism and behavioural components of repeated escape performance, in the broader project, we also measured how personality (“bold – shy” axis; “anxiety - risk taking” axis) could affect escape response performance. Including this additional analyses is needed to gain a deeper understanding of how physiological and behavioural aspects affect escape response.