The Herpetological Journal

pp.79-84

Authors: Adrian Hailey And John P. Loveridge

Abstract: It is difficult to devise physical models which precisely mimic the body temperatures (T_b 's) of large reptiles in the field. Studies of large reptiles have the compensating advantage that individuals can be fol lowed for long periods, so that translocated individuals can be used as ' living models'. We compare T_b's of two tortoise species in an enclosure in Harare (altitude 1500 m) with those in the field at Sengwa (900m), where mean air temperatures were about 5°C higher. Kinixys spekii, which occurs naturally near Harare, had similar T_b 's at the two sites (means 27.6 and 27.0°C, respectively). Geochelone pardalis had significantly lower T_b 's in Harare (29. 1 °C) than at Sengwa (32.6°C), even though activity was shifted towards midday in Harare. The inability to reach high T_b during activity may explain the absence of G. pardalis near Harare, and the distribution of this species in southern Africa.