Alometria reprodutiva de Podocnemis unifilis (Testudines: Podocnemididae) na várzea do baixo Rio Amazonas, Santarém, Pará, Brasil

Abstract

The body size of the organisms represents an important parameter, which may have consequences on their ecology, reproductive activities, evolution and development. Allometry relationship is the study of the size (or growth) of a body part in relation to the final size (or growth) of the organism. This study analyzed the allometric relationships between females of Podocnemis unifilis (Troschel, 1848), their eggs and hatchlings, and between nest features and the clutch in the flooded forest portion (várzea) of lower Amazon River, Santarém, state of Pará, Brazil. Podocnemis unifilis clutches' were monitored in the Tabuleiro da Água Preta during the reproductive cycle of 2009. The females found nesting were measured and the physical features of the nests were measured, and the latter were also marked with numbered stakes. The eggs and hatchlings of these nests were removed and counted, and their biometry was performed. The female parameters analyzed (straight-line carapace length and mass) were correlated with almost all the egg and hatchling variables, with the exception of the egg length and the hatchling mass. Future studies directed to the better understanding of how the environmental features influence nest features can be applied, being useful for more effective applications of management actions for the species.