A bioacústica na reintrodução do periquito-do-sertão (Eupsittula Cactorum)

Abstract

Communication is fundamental for the survival of animals and can be genetically defined (innate) or socially learned. During the process of vocal learning small modifications occur in the vocalizations, producing geographical variations. Eupsittula cactorum, as well as other Psittaciformes, present social learning and have rely strongly on acoustic communication for social interactions. The species is a common target for trafficking, and recovered individuals have been constantly released into the wild. The present work aims to obtain information on the acoustic communication of the species and apply it on releasing protocols. We obtained recordings from four populations in Brazilian north-east and individuals under recovery at CETAS-Fortaleza. The voices of the natural populations were used to describe the vocal repertoire, where geographical variation was detected through a multinomial regression. Captive individuals were recorded before and after quarantine and monthly after release. In the presence of geographical variation, we tested the vocal similarity of the released individuals to the release areas using a multinomial regression, applied the acoustic parameters in a PCA and calculated the Euclidian distance of each vocalization to the origin and a polynomial regression to check for vocal convergence. Nine vocalizations were described, associated to specific behaviors, with no semantic redundancy. The populations presented dialects and the classification pointed that several individuals released by CETAS were released in areas that are linguistically distant. The experimental group converged vocally during quarantine, also converging to the local dialect of the region where they were released. Eupsittula cactorum demonstrated to have complex communication with vast vocal codification, yet flexible and capable of abridge the vocal differences between individuals allowing efficient communication, facilitating the reintroduction process. We suggest the use of vocalizations to determine the appropriate areas for releasing and that individuals can be previously trained with the regional dialect in order to minimize cultural differences between sylvatic and released individuals, improving individual socialization.