MICROHABITAT INFLUENCE ON PREDATION RATE IN POPULATIONS OF Bothrops jararaca (WIED, 1824)
Matuoka MA1, Banci KRS1, Dall'Occo PL2
1 Laboratório Especial de Ecologia e Evolução, Instituto Butantan, Brasil; 2 Laboratório de Taxonomia e Ecologia Animal, Universidade Presbiteriana Mackenzie, Brasil
Introduction: Snakes consist of a diverse group, with predators from several taxa, among which birds and mammals are the most significant ones. Studies related to predation on these animals in nature are scarce, due, mainly, to the difficulty on finding them in their natural habitats. For this reason, studies concerning this aspect are fewer than those about other ecological aspects such as reproduction, defense and diet. Also, the existing studies of predations were made related to patterns and colorations or aspects like head shape, however no one compares the microhabitats occupied by these animals. It can also be applied to one of the most common species in Brazil, Bothrops jararaca, a semi-arboreal and nocturnal snake, characteristic from the Atlantic Forest, it has medical relevance due to its potent venom. A manner to circumvent this low frequency of encounters is to use snakes replicas made with plasticine, which may register the predation imprints, allowing to identify if they were made by mammals or birds, also they have the great advantage of their use in large scale.
Objectives: To compare the predation rates upon Bothrops jararaca replicas set on trees and on the ground.
Methods: The study was conducted in 2014, along September and October in the “Fontes do Ipiranga” and “Cantareira” State Parks, where three samplings were made in each area resulting in an amount of 360 replicas. The replicas were distributed along three transects in each park in a random classification that chose ground or tree as their microhabitat. They remained in the field for 48 hours before collected and analyzed for imprints.
Results and Discussion: The collection of data revealed attacks made both by birds and mammals. Nevertheless, there was no significant difference on the predation rates according to the microhabitat indicating absence of microhabitats influence on the predation rate on Bothrops jararaca. This might be due to factors as a restrict period of experimentation and a similar foraging mode of predators from both microhabitats. However, once the study is pioneer, more research must be done with this same approach about the ecology of snakes to be better understood.
|11 - SYSTEMS BIOLOGY||21th Annual Scientific Meeting of Instituto Butantan.|