História natural de Tupinambis merianae (Squamata, Teiidae) na Estação Ecológica do Taim, extremo sul do Brasil

Abstract

The genera Tupinambis comprises the largest lizards of America, which could reach 500 mm of corporal length. Two species possess wide distribution in South America (T. teguixin and T. merianae), while the others are restricted the specific biome (Amazonian Forest, Savannah and Chaco). The species T. merianae have the widest distribution of the gender, from the south of the Amazonian Forest to the north of Patagonia, at the east of Andes. In the present study, 640 h of sampling were accomplished (320 h of observations in the area to analyses of behavior; 320 h of observation along transects), in the total of 64 days. In the summer, there were no registrations of active lizards before 7:37 in the morning, nor after 17:43 of the afternoon. The use of community hibernacula was registered for the winter dormancy, being the burrows dug in cemented constructions used more frequently in the observation area. As for the seasonal activity, the first individuals emerged in August and the last ones returned to the dormancy in April. The emergency of the population demonstrated to be protandric, with adults emerging before juvenile. In the period after emergency, the males were basking in aggregations of up to 13 individuals, which changed of positions through audible resonant signs. Besides, sibilated sounds can be emitted in stress situations or agonistic interactions. There was significant difference of activity among the different certain periods in this study, along the months (F = 16.6; p <0.01), being October and December the months with registration of the individuals' larger activity. There was fluctuation in the population size and in the activity of the different age classes along the months. The minimum home range for three males and two females (variation from 0.05 to 20.29) were registered. The area of use of the animals did not differ along the months, but it was possible to observe gregarious behavior during the nine months of study.