LAUSR

Podocnemis unifilis is threatened by decline of their populations due to the capture and consumption of adult females and their eggs; to mitigate this decline in population has been implemented community management programs, which include incubating, captive breeding and release of juveniles in temporal pools. However, these programs do not have control on sex ratio of hatchling that are being returned to the river. This study seeks to determine the sex ratio in hatchling of P. unifilis by morphometric methods, as an alternative to invasive procedures of sex determination technique. Was recorded the mean size clucth 31,1 eggs with 70% hatching success and a mean incubation period of 72-83 days. Histological analysis of gonads of 35 individuals allowed the classification of 14 male and 21 female neonates. The result of the PCA completed with morphometric measurements of the juveniles showed a trend in the separation of the sexes, with the carapace length, carapace width and carapace plastron measured as major contributors to this trend, and a percentage classification of 77.8%. However, the statistically significant difference (p <0.05) between the morphometric measures respect to the separation of the sexes was not found.