Hypothalamic nonapeptides (vasopressin-vasotocin (AVT), oxytocinisotocin) play a crucial role in generating behavioral diversity, fostering temporal behavior patterns that align with the season, immediate social context, and physiological state of the animal. In anurans, the emission of vocal calls in different and complex contexts is an important behavior for successful breeding that can be modulated by AVT. Boana pulchella is a South American hylid frog, widely distributed in Uruguay. During breeding, males congregate in choruses and emit three distinct note types to attract females. In this species, the calling sequences are dynamic and can be modulated by social feedback. Our aim was to investigate how AVT modulates changes in male calling behavior. For this purpose, we conducted pharmacological experiments in the field with three xperimental groups of calling males, injecting AVT, AVT antagonist (MC), and saline. We found that the AVT antagonist reduces calling probability and changes the spectral properties of the acoustic signals. Deepening our understanding of how nonapeptides modulate calling behavior appears to be the first step in elucidating the neural mechanisms underlying social interactions in complex contexts.