Revista Chilena de Historia Natural 82 (4): 577-588, 2009
RESEARCH ARTICLE
Range structure, microhabitat use, and activity patterns of the saxicolous lizard
Tropidurus torquatus (Tropiduridae) on a rock outcrop in Minas Gerais, Brazil
Although Tropidurus is a widely distributed lizard genus in South America
and the Galapagos Islands, studies on space use and spatial distribution are scarce. We studied the home range structure of the
saxicolous lizard Tropidurus torquatus based on the inland population of a rock outcrop in Minas Gerais State,
southeastern Brazil. Lizards were individually marked and observed during reproductive and non-reproductive seasons. Using the
minimum convex polygon method, we found that average total range size of males during the reproductive season was larger than that
of females, and that both had -similar total range sizes in the non-reproductive season. The harmonic mean method showed that
males have a larger home range size than that of females during both seasons. As expected for a polygynous species, the average
number of males whose total ranges overlapped those of females tended to be higher in the reproductive season than in the non-
reproductive season. Intrasexually, the number of females whose total ranges were associated with those of other females was also
higher in the reproductive season than in the non-reproductive season. For males, this number remained low in both seasons,
suggesting that males use more exclusive areas, whereas the smaller total ranges of females apparently sustain a higher density of
individuals during the reproductive season. Frequency of microhabitat use in relation to vegetation increased in the non-reproductive
season and the activity patterns of lizards shifted from bimodal in the reproductive season (rainy period) to unimodal in the non-
reproductive season (dry period). Thus, the range structure, microhabitat use, and activity patterns of the T. torquatus
observed here were all influenced by the time frame affecting their spatial ecology.
Key words:
activity times, habitat
use, home range, total range, Tropidurus
