A novel hyperbaric swimming respirometer allows the simulation of varying swimming depths in fish respirometry studies.

The understanding of swimming physiology and knowledge on the metabolic costs of swimming are important for assessing effects of environmental factors on migratory behavior. Swim tunnels are the most common experimental setups for measuring swimming performance and oxygen uptake rates in fishes; however, few can realistically simulate depth and the changes in hydrostatic pressure that many fishes experience, e.g.

Metabolic costs of spontaneous swimming in Sprattus sprattus L., at different water temperatures.

Oxygen uptake (MO2; mgO2 fish-1h-1) of fish groups was measured at temperatures between 10-19°C in an intermittent-flow respirometer to quantify the metabolic costs of spontaneous swimming patterns in the small clupeid Sprattus sprattus. Movements of individual fish within the school were tracked automatically during respirometry. Oxygen uptake was then related to mean swimming speeds and the number of sharp turns (>90°), which are common behavioural elements of spontaneous swimming in clupeid fish.