Reproductive biology of Melanophryniscus montevidensis (Anura: Bufonidae) from Uruguay: reproductive effort, fecundity, sex ratio and sexual size dimorphism

We analyzed the reproductive traits of a population of Melanophryniscus montevidensis. The reproductive events were associated to rainfalls. Males called from dawn to late night, were more abundant than females, and adopted alternative tactics to find partners (active search). Females were larger than males, and had mature oocytes and lipid reserves after spawning; they showed no association between size and fecundity. As an explosive breeder, females are prepared all year long for reproduction. Several individuals revealed high site-fidelity for breeding. Knowledge about breeding pattern could help to propose suitable and efficient in situ conservation measures for this endangered species.