Temperamento e respostas ao estresse em psitacídeos neotropicais: implicações no manejo e no bem-estar

Abstract

The Neotropical region harbors the greatest diversity of birds in the world, with Brazil accounting for about 1,971 species, 256 of which are threatened with extinction. Among these, parrots (family Psittacidae) stand out, with 83 species resident in the country, many of them severely affected by the illegal wildlife trade. Species such as Pionus maximiliani, Primolius maracana, and Psittacara leucophthalmus are frequently rescued and kept in rehabilitation centers, where they face conditions that can cause physiological and behavioral stress. Although widely distributed, few studies have investigated how temperament influences stress responses, which directly affect animal welfare. These events are common and can lead to behavioral and physiological changes that impact welfare. Although stress responses vary among individuals, the relationship between these responses and temperament remains poorly understood in Neotropical parrots. This study evaluated 45 individuals from the species P. maximiliani (n=18), P. maracana (n=12), and P. leucophthalmus (n=15). The animals were subjected to behavioral tests (novel object test and human response test) to measure temperament dimensions. Five dimensions were identified: activity, boldness, anxiety, neophobia/neophilia, and proximity to humans. The individuals were also subjected to manual restraint, during which blood samples were collected and physiological (heterophil-to-lymphocyte ratio) and behavioral variables were recorded, including bioacoustic analyses. The analysis revealed two main stress response profiles: high/low response intensity and active/passive avoidance. Bolder individuals showed more balanced physiological responses, with lower cloacal temperatures and respiratory rates, while more active individuals showed lower behavioral response intensity, with fewer vocalizations and less aggressiveness. Differences among species were also observed: P. leucophthalmus displayed more passive behavior, with elevated physiological parameters, while P. maracana showed higher reactivity, expressed through intense vocalizations and escape attempts. These results demonstrate that individual factors, such as temperament, significantly influence how parrots respond to stress in captivity. Identifying these profiles can improve management and rehabilitation practices, increasing welfare and reintroduction success. Thus, integrating behavior, temperament, and physiology is essential for conservation strategies and individualized management of threatened species.