Biologia alimentar de hilídeos simpráticos (Anura, Hylidae) em um ambiente sazonalmente alagável na Amazônia Brasileira

Abstract

Anurans play fundamental roles in ecosystems, directly influencing the dynamics of the biological communities they inhabit. Studying the trophic ecology of this group helps us understand how these species interact with other organisms and their surrounding environment. This study focuses on analyzing the trophic ecology of sympatric amphibians from the Hylidae family in a floodplain region of the Brazilian Amazon. The research aimed to describe and compare the diet composition of six anuran species from the Hylidae family (Boana raniceps, Boana punctata, Dendropsophus leucophyllatus, Dendropsophus walfordi, Lysapsus bolivianus, and Sphaenorhynchus lacteus). The study sought to answer the following questions: (1) What is the degree of similarity in the diet of the studied species? (2) What is the degree of dietary specialization among the species? (3) What is the trophic niche size of these species? (4) What is the relationship between predator size and the size of consumed prey? The study was conducted in a floodplain environment at Lake Maicá, in the municipality of Santarém, Pará, from April to August 2023. The stomach contents of 334 anuran specimens were analyzed, with 254 containing some type of content. The diet was mainly composed of arthropods, with the order Diptera being the most common prey category, except for B. raniceps and S. lacteus, which predominantly consumed Formicidae and Orthoptera, respectively. There was similarity in diet composition among some species, and trophic niche overlap was observed, highlighting the importance of Diptera as a prey category for certain Hylidae groups. Most species exhibited broader trophic niches, with diets considered generalist. The exception was S. lacteus, which presented a diet specialized in ants. A positive correlation was observed between individual size and the volume of prey consumed. This study provides new insights into the feeding ecology of Amazonian anurans, highlighting adaptations and interactions that enable their coexistence in a complex floodplain environment.