Definindo espécies de serpentes prioritárias para conservação: aspectos ecológicos e evolutivos

Abstract

The current scenario of biodiversity loss crisis and the lack of conservation resources show that conservation efforts are needed to direct actions to protect species at greater risk. Currently, the most widely used method for electing endangered species is the one proposed by IUCN. However, recent approaches proposed such prioritization based on scores, considering aspects of environmental vulnerability (e.g. habitat loss), life history (e.g. habitat and diet specializations, size, fecundity) and how each species is evolutionary distinct in the group. In this work, we propose a preliminary prioritization index for a tribe of Neotropical snakes: Xenodontini. We analyzed three ecological variables of the tribe: maximum body size, mean fecundity and diet amplitude, that were calculated to generate an ecological singularity index and then a prioritization index for each Xenodontini species. Index of prioritization (PI) was calculated for 47 species of the tribe. Although it is a preliminary index, some of the representatives of the tribe presented high scores. Therefore, it is necessary to gather more data and variables to generate a complete index. Finally, such approach is an innovation and it is promising when the object study is a snake group, as it is known that these species are constantly threatened both by their ecological peculiarities (eg. ectothermia, dependence on certain prey, restricted geographical distribution for many species) and by man's threats (e.g. dislike, misunderstanding of their importance in ecosystems, trafficking).