EFFECT OF TEMPERATURE ON OXYGEN-CONSUMPTION AND HEART-RATE OF THE AUSTRALIAN CRAYFISH CHERAX-TENUIMANUS (SMITH)

1. 1. Oxygen consumption at 18°C was 60% of the rate at 22 and 26°C. 2. 2. Critical points, where the rate of oxygen consumption changed, were defined at 22°C (2.89 mg DO) and 26°C (3.46 mg DO). Linear regressions were fitted showing that oxygen consumption declined significantly (81.5% ±4.5) below the critical point. 3. 3. Oxygen consumption was proportional to weight. Allometric relationships resulted in variable temperature-related coefficients for respiratory dependence on weight, a reflection of the crayfish adaptation towards re-establishment of a new equilibrium state. 4. 4. Heart beat rate was lower at 18°C, and highest at the acclimation temperature (22°C). Stress at 26°C was evident. © 1989.