Scaling of oxygen consumption of Lake Magadi tilapia, a fish living at 37 degree C

Rates of oxygen consumption were measured in the geothermal, hot spring fish, Oreochromis alcalicus grahami by stopped flow respirometry. At 37 degree C, routine oxygen, consumption followed the allometric relationship: Vo sub(2)=0.738 M super(0.75), where Vo sub(2) is ml O sub(2)/h and M is body mass (g). This represents a routine metabolic rate for a 10 g fish at 37 degree C of 0.415 ml O sub(2)/g/h (16.4 mu mol O sub(2)/g/h). Acutely increasing the temperature from 37 to 42 degree C significantly elevated the rate of O sub(2) consumption from 0.739 to 0.970 ml O sub(2)/g/h (Q sub(10)=1.72). In the field, O. a. grahami was observed to be 'gulping' air from the surface of the water especially in hot springs that exceeded 40 degree C, O. a. grahami may utilize aerial respiration when O sub(2) requirements are high.