Mecanismos de defesa em Crotalus durissus (Linnaeus, 1758) (Serpentes, Viperidae) em cativeiro e suas interações intraespecíficas

Abstract

The variety of defensive responses and the influence they exert on these are not being clear, because of that it is advantageous to obtain more information about the species. Thus, it was elaborated a list of defensive behavior and the description of each act. We also related abiotic, physical and social factors with the displayed answers. We observed 54 adult specimens and divided into groups of five and kept for 10 consecutive days.The experiments were carried out in three phases (approach, apprehension and handling), excluding the handling, the phases were repeated three times and in two enclosures. On apprehension it held clamping of individuals in two locations of the body to exert different levels of stress. We identified 20 behavioral acts, classified by passive and active, and in the approach phase there were less diversity of defensive actions (10) than in apprehension phase (17) and handle phase (18). Analyzing the three levels of stress, we observed higher frequency of active responses at prehension of posterior region of the head follow by body prehension and the lower frequency during approach. Regard to the enclosures, it was found more passive behavior at individuals into a collective enclosure than in individualized. There was a small influence of temperature on responses, the layers analyzed set the model for the significance of the results of the enclosures. This study characterized the defensive behavioral repertoire of Crotalus durissus snake, identified and described two new anti predatory acts (jump and hiss). So, we can understand their patterns of action and also assist at preventive measures to avoid accidents during the activities in the field and in the laboratory. The study also confirmed the influence of abiotic factors on the defensive responses and recorded the difference in behavior when individuals were being individualized and with other specimens. Therefore, we can infer some interaction between the specimens, this had not been described before in this species.