The Herpetological Journal

pp.559-567

Authors: Ronald E. Willemsen

Abstract: The activity patterns and body temperatures of T. hermanni and T. marginata were studied in the Peloponnese (southern Greece) during May, June, August and October 1984.
T. hermanni:
In May the daily activity patterns of T. hermanni were uni modal , in June and August they were bi modal. In August during the afternoon the activity increased significantly. in October the activity was very low. In August basking decreased significantly and mating increased significantly. During these four months no significant differences in body temperatures were found. In May a maximum body temperature of 35°C was found; in feeding tortoises a maximum temperature of 34°C. After May no temperatures over 32°C were found.
T. marginata:
In May and June the activity patterns of T. marginata were bimodal with the highest activity during the afternoon. In August an uni modal low activity pattern was found during the afternoon. In October the activity of T. marginata was uni modal and shifted towards the middle of the day. Sexual activity was seen in October only. Body temperatures in all T. marginata samples were significantly higher than those in T. hermanni. During May a maximum body temperature of 36°C was found in basking tortoises, a maximum of 37°C in feeding tortoises. The trend towards lower body temperatures in summer was greater in T. marginata than in T. hermanni. Body temperatures found in feeding tortoises in October equalled those found in May.
Ecological Consequences:
In southern Greece the habitat separation between T. hermanni and T. marginata can be explained by morphological differences and a higher body temperature tolerance in T. marginata. Differences in the annual cycle of activities might also be of importance as regards the habitat separation between both species.