Flight capacity and human aversion in captive Amazon parrots: Related factors and the effects of pre-releasing training

The maintenance of parrots in captivity, caused by the illegal traffic and illegal ownership of these animals, makes them lose essential abilities for free-living survival, such as flight capacity and human avoidance, which hinders the success of reintroduction programs. Here, we assessed the influence of physical features (body weight, wing load, and plumage condition), endoparasites, and a training protocol on flight capacity and aversion to humans in captive parrots which were candidates for reintroduction. In addition, we assessed the relations of flight capacity and aversion to humans with the parrots' temperament. Therefore, 38 parrots were submitted to a flight training and human aversion training protocol for 10 weeks. The following variables were registered over time for each animal: human aversion score, flight score, flight time (in s), and latency to flight (in s). A GLMM was adjusted to analyze the flight performance of the parrots over time, as well as the effects of body weight, wing load, occurrence of intestinal parasites, and plumage condition. Pearson correlation coefficients were applied to evaluate the association of parrots' temperament with flight capacity and responsiveness to humans. We have observed a significant increase in the flight time (P = 0.0016) and flight score (P < 0.0001), as well as in the human aversion score (P < 0.0001). Factors that influenced flight capacity were body weight, wing load, and plumage condition. The temperament dimension neophilia was negatively correlated to the human aversion scores, with neophiliac parrots showing less aversion. The risk-taking dimension was negatively correlated to flight capacity, i.e. risk-averse parrots had better flight capacity. Using the training procedures described in this study, it was possible to improve flight capacity and increase aversion to humans, these abilities are essential for the animals' survivorship in wild. Furthermore, we identified factors (body weight, wing load, plumage condition, and the temperament dimensions neophilia and risk-taking) that must be treated cautiously and that aid in the selection of individuals which are suitable for reintroduction, an important process for the conservation of endangered species.