The Antarctic fish Pagothenia borchgrevinki has been shown to be able to survive at raised temperatures. However, survival at elevated temps is linked to tissue hypoxia (inadequate supply of oxygen) and is important in the early stages of acclimation. Acclimatised fish (-1°C and 4°C) were placed in a closed box respirometer, and subcutaneous ECG electrodes measured heart rate and breathing rate, to determine the fishes response to hypoxia at increased temperatures.
Robinson, E., Egginton, S. And Davison, W. 2010. Warm-induced bradycardia and cold-induced tachycardia: mechanism of cardiac and ventilatory control in a warm-acclimated Antarctic fish. Polar Biology doi: 10.1007/s00300-010-0891-z