Thermal equilibration rates in relation to heartbeat and ventilatory frequencies in largemouth blackbass, Micropterus salmoides

Abstract

Relative heating and cooling rates were determined simultaneously with heart and opercular beat rates in bass subjected to sudden increases or decreases of 10–20°C in ambient water temperature. 1. 2. Cooling rates exceeded heating rates up to 90% of the equilibrium temperature, but equilibrium was usually reached sooner during heating. 2. 3. Heart and opercular beat rates were closely synchronized (1:1) during heating and cooling. 3. 4. Heart and opercular beat rates were greater for a given temperature during heating than during cooling; however, the initially greater rates during cooling may contribute to initially faster cooling.