Accuracy of the Haldane method as an indirect measure of metabolism.

Metabolic rates of barn owls increased as ambient temperature decreased below the thermoneutral zone. The Haldane method was as reliable as an O2 analyzer in measuring the metabolic rates of captive barn owls. However, at lowered ambient temperature (below 5 degrees C) there was a slight disparity in the metabolic rates determined by the two methods. The Haldane method has the potential of being used in a field situation (i.e. it is reliable, portable and relatively inexpensive).