SEASONAL CHANGES IN THE STANDARD RATE OF OXYGEN CONSUMPTION OF FISHES

Abstract

The standard rate of oxygen consumption for brook and brown trout acclimated to 10 °C and exposed to natural daylight varied seasonally. For male brook trout, standard oxygen consumption increased from a low of 30 mg/kg hour during March and April to a maximum of 63 mg/kg hour during the late fall spawning period. The standard rates of the females approximated those for males. For male brown trout, standard oxygen uptake increased from a value of approximately 20 mg/kg hour during the winter and spring months to a high of roughly 30 mg/kg hour during the fall spawning period. Little change was observed in the standard oxygen consumption of female brown trout.