A review of adult salmon maximum swim performance.

Abstract

Salmonids undertake long and strenuous migrations, which require aerobic endurance and anaerobic burst swimming. Anthropogenic activity and natural disasters can make already challenging migrations even more difficult. This reinvigorates a central question: what is the maximum swimming capacity of adult salmon species across environmental conditions? We synthesized literature on adult salmon swim performance (Oncorhynchus spp., and Salmo salar) to unfold what is known about how biological (sex, body size) and physical (temperature) factors affect swimming in adult salmon. Maximum anaerobic swimming—bursting, jumping, leaping—are among the least studied swim performances in adult salmonids. Commonly, swim performance has been measured using swim flumes, but evidently adult salmon can swim faster in the wild than this setup can capture. We show that larger fish can outswim smaller ones, and that thermal sensitivity of swimming differs inter-and -intra-specifically. Unresolved are how anaerobic swimming differs across temperatures, between males and females and across maturity-states. This information can be used to inform exercise physiology research and future management and mitigation actions necessary to conserve these iconic, economically valuable species.