Thermoregulation in crocodilians—I. Head-body temperature control in the papuan-new guinean crocodiles, Crocodylus novaeguineae and Crocodylus porosus

Abstract

1. 1. Head-body temperature differences were found to occur with both solar and radiant heating in Crocodylus novaeguineae and C. porosus. 2. 2. Both species of crocodiles were found capable of reducing head and body temperature by physical, behavioral and possibly physiological means with the most effective method being the seeking of cooler environments such as shade and water. 3. 3. After preferred temperatures had been reached, there appeared little difference between head and body temperature and the differences found would be of little ecological significance in both species, although head temperature was regulated more precisely. 4. 4. Thermal preferenda and voluntary maxima for both head and body temperature are reported for each species.