Ecologia reprodutiva da rã allobates sumtuosus: um estudo de campo sobre os determinantes da atividade temporal e sucesso do macho.

Abstract

Poison frogs (Dendrobatidae) show complex, elaborate, and variate breeding behaviours. Hypothesis-testing approaches are relevant to understand the effect of ecological factors on breeding activity and reproductive success under realistic, field-based conditions. In this study conducted in Central Amazonian forests during an entire rainy season, we aimed to 1) characterize the reproductive biology of Allobates sumtuosus; 2) test the effect of environmental cues on diel calling activity; and 3) test the effect of intrinsic and extrinsic predictors of male reproductive success. Male vocalization activity peaks in the early morning and late afternoon, and is negatively influenced by environmental temperature. There are sexual differences in behavior, size and color: males were territorial, had smaller body sizes than females, and white vocal sac and belly in contrast to females whose ventral surface was yellow. Adult individuals did not have a significant increase in body size from one breeding season to the next. Mating pairs showed an elaborate courtship behaviour during which females deserted in 71.4% of the observations. Eggs were deposited in communal nests on dead leaves on the leaf litter, and these nests contained several other spawnings, with asynchronous-developing eggs from the same, territory-owner male. Only males showed egg and larvae attendance, transporting tadpoles to waterbodies ca. 20 days after oviposition. An adult male was found near an amplecting pair inside a nest, constituting the first indication of male satellite behavior in the genus. Approximately 76% of the egg masses reached the tadpole stage and were transported. The mating call of the species is first described and consists of continuous, low-amplitude notes with irregular temporal arrangements separated by irregular silence intervals. Male reproductive success was uneven and not predicted by body size, territory tenure, and territory size, suggesting that female choice and reproductive output do not depend on these traits.