Canibalismo de descendentes inviáveis por serpentes da família Boidae: por que as mães se alimentam de seus filhotes?

Abstract

Intraspecific predation or cannibalism is a phenomenon characterized by the total or partial consumption of another individual belonging to the same species. In maternal cannibalism, the parent female ingests items from the litter such as eggs, embryos, embryonic attachments or young, shortly after parturition or laying. This behavior can be considered as a framework of parental care, avoiding drawing the attention of predators and the proliferation of pathogens to healthy offspring, or the replacement of nutrients for the puerperal female, since eggs and neonates are rich in nutrients and pregnancy demands extremely high energy consumption. The purpose of the present study is to provide general information about reproduction, through video recordings, focusing on maternal cannibalism observed in snakes of the Boidae family. Videos of two females of the genus Epicrates, E. assisi (caatinga rainbow boa) and E. cenchria (amazônia rainbow boa), puerperal from the same breeding site on different dates, were analyzed. Seven videos from the internet, filmed between 2010 and 2022, were also analyzed. Three videos contained females of E. cenchria, three contained females of Eunectes murinus (green anaconda) and one contained a female of E. notaeus (yellow anaconda). We conclude that there is cannibalism of unviable offspring by the progenitors of the analyzed species. However, there are still controversies regarding the hypotheses related to this behavior. The strongest hypothesis concerns the utilization of nutrients. On the other hand, the literature substantially supports the hypothesis of parental care.