Body condition and diet of the dyeing poison frog Dendrobates tinctorius (Cuvier 1797) (Amphibia: Dendrobatidae) from the eastern Brazilian Amazonia

The present study adds new data on the natural history of Dendrobates tinctorius. We conducted our fieldwork during the rainy season of the years 2018 and 2019 in two protected areas (Parque Natural Municipal do Cancão–PNMC and Reserva Extrativista Beija-Flor Brilho de Fogo–REBFBF) in the state of Amapá, Brazil. Through active visual searches we sampled 22 individuals of D. tinctorius, of which 10 were counted for the population of PNMC and 12 for the population of REBFBF. We calculated the Body Condition Index (BCI) for all individuals and, for dietary data, each frog's stomach was flushed. Females from the REBFBF were larger than males when compared to the PNMC population. BCI of females from the REBFBF showed higher values than males. Gravid females of both populations showed higher BCI. Retrieved stomachs revealed a total of 290 prey items divided into four main taxonomic categories of Arthropods. The Index of Relative Importance revealed that ants of the genus Solenopsis were the majority of the diet, and mites represented only 4.86%. The niche breadth for both populations was narrow, indicating a specialist diet, as expected for the species. Our study evidences the importance of integration between BCI and dietary aspects.