Dieta de Podocnemis unifilis Troschel 1848 (Testudines: Podocnemididae) no rio Andirá, Barreirinha, Amazonas, Brasil

Abstract

Amazonian aquatic turtles are mostly omnivores and opportunists, seeking their food mainly in flooded forests during river floods. All these characteristics allow these animals to respond more easily to the impacts suffered in their natural habitat. Knowledge of their diet can help us identify important food resources for turtles, which favors the protection of their feeding areas and the conservation of species, which are important sources of protein for riverine and indigenous peoples. This study aims to understand and identify the composition of the diet of the red-necked turtle (Podocnemis unifilis) in the Andirá River, Amazonas, Brazil, from 2019 to 2021. We used data from the capture of P. unifilis specimens; the captured animals were subjected to stomach washing (flushing) to determine the frequency of occurrence (FO%), relative frequency or percentage volume (VP%) and the food index (IAi) of the food items ingested by the turtles. We found more plant material in the stomach content of P. unifilis, with 44.45% FO, while animal material was 31.12%. Of the ingested diet, 32.12% of VP corresponds to plant material and 9.83% of VP to animal material. Among the most important food items in the diet of the tracajá, the following stand out: plant material, fruits (21.86% IAi) and seeds (6.67% IAi) and among the animal materials, the most important items were crustaceans (4.89% IAi) and mollusks (3.62% IAi); however, the digested material presented the highest percentage in the food index, which was 58.00%. The most representative plant family of the items found and identified was Fabaceae, and among the animals we identified individuals of Belatostomatidae (insects) and Trichodactylidae (crabs), Hyriidae (mollusks) and Characidae (fish).