Vocalizations emitted by the rare and endangered painted tree rat, <i>Callistomys pictus</i> (Rodentia, Echimyidae)

Abstract Bioacoustics is a valuable tool for conserving threatened species, enabling the identification of population patterns and activity in cryptic, elusive animals. We studied the acoustic signals using opportunistic acoustic recordings of Callistomys pictus , an endangered small mammal endemic to Brazil’s heavily impacted Atlantic Forest. We described, classified, and mathematically confirmed at least three distinct vocalization types in its repertoire – whine, warble, and whistle – which are compatible with vocalizations by other closely related taxa. These results address critical gaps in knowledge of its behavior and vocal communication, offering insights that can significantly aid its conservation.