Reproductive ecology of the nurse frog Allobates sumtuosus : a field study of the determinants of temporal activity and male mating success

Studies on the reproductive biology of dendrobatoids have demonstrated that polygamous mating is an evolutionarily stable strategy for this group. Consequently, research that provides new data within this clade is essential for understanding the broader evolutionary and conservation implications of these behaviours. In this study conducted in Central Amazonian forests during an entire rainy season, we aimed to understand the patterns of the reproductive biology of Allobates sumtuosus, including testing the effect of environmental cues on diel calling activity, and the effects of intrinsic and extrinsic predictors of male reproductive success. Our results show that male vocalization activity peaks in the early morning and late afternoon and is negatively influenced by environmental temperature. Mating pairs showed an elaborate courtship behaviour during which females deserted males in 71.42% of the observations. Eggs were deposited in communal nests on dead leaves in the leaf litter, and these nests contained several other spawn, 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. Approximately 76% of the egg masses reached the tadpole stage and were transported. The courtship call of the species is first described and consists of continuous, low-intensity continuous 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.