Food and energy requirements of captive barn owls Tyto alba.

Food and energy requirements of captive barn owls were determined at 5, 15 and 25 degrees C. Food consumption, gross energy intake, dry matter intake, and existence metabolism increased as ambient temperature decreased. Barn owl energy assimilation efficiencies at the three test temperatures were approximately 78%. An increase in bioenergetic parameters might be anticipated when a bird is cold-stressed and must increase its metabolism for thermoregulation.