NESTS CHARACTERIZATION AND SEXUAL IDENTIFICATION OF PODOCNEMIS EXPANSA, AMAZON TURTLE

Authors

  • Ana Karla Gonçalves Kagueiama Universidade Federal do Tocantins
  • Adriana Malvasio
  • Heitor Campos de Sousa
  • Fábio de Jesus Castro
  • Adson Gomes de Ataídes
  • Roberto Leandro da Silva

DOI:

https://doi.org/10.20873/uftsupl2021-12549

Abstract

Climate change and the impacts that the planet has been suffering from human actions make ecological and biodiversity monitoring essential. Studies on egg incubation temperature-dependent sex determination in turtles present several challenges, one of which is related to the sexual identification of hatchlings. The external morphological characteristics of newly hatched Podocnemis expansa, which show sexual dimorphism, will only be noticeable after a few years of life. Histological study of the gonads is a reliable way to differentiate males and females in hatchlings. This study aimed to evaluate the influence of physical and geomorphological aspects of P. expansa nests and relate them to the sex determination of the species on the beaches of the Rio Xingu/PA. Histological analysis resulted in a sex ratio of 0.17:1 males/females, totaling 103 males, 609 females and 60 unidentified. Nesting areas with smaller particle size fractions (fine/fine average) and lower average incubation temperature had a higher number of males. There was a predominance of females at higher temperatures, where the particle size fraction was higher (medium/coarse). Geometrical morphometry of the hatchlings's carapace identified morphometric differences between males and females, results that may reduce the number of euthanized offspring destined for histology.

Published

2022-04-10

How to Cite

Gonçalves Kagueiama, A. K., Malvasio, A., Campos de Sousa, H., de Jesus Castro, F., Gomes de Ataídes, A., & Leandro da Silva, R. . (2022). NESTS CHARACTERIZATION AND SEXUAL IDENTIFICATION OF PODOCNEMIS EXPANSA, AMAZON TURTLE. DESAFIOS - Revista Interdisciplinar Da Universidade Federal Do Tocantins, 8(Especial), 85–91. https://doi.org/10.20873/uftsupl2021-12549