Swimming smarter, not harder: fishes exploit habitat heterogeneity to increase locomotor performance.

Quantifying the intricate relationship between locomotion, energy expenditure and environmental heterogeneity is pivotal for elucidating the ecological and evolutionary changes in locomotor performance in fishes. This Commentary synthesizes existing research to offer a perspective on how fishes actively exploit complex environments to enhance their locomotor efficiency. Contrary to conventional portrayals of fishes as passive responders to environmental stressors, empirical evidence supports the idea that fishes employ sophisticated strategies to navigate diverse hydrodynamic landscapes. Here, we show clever ways fishes bend the rules of a non-linear speed-energetics curve to save energy below and above optimal cruising speeds. The findings from these behavioral adjustments hold broader implications for understanding fish performance under dynamic environments and conserving fish populations.