Human-Aversion Training Trials Aim to Prepare Confiscated Yellow‑naped Amazons for Release

Researchers in Costa Rica tested a human-aversion training (HAT) protocol on confiscated Yellow‑naped Amazon parrots (Amazona auropalliata) as part of preparation for release. The study notes that “Researchers tested a human-aversion training (HAT) protocol intended to reduce attraction to people in confiscated Yellow‑naped Amazon parrots (Amazona auropalliata) prior to release. Twelve birds received 36 HAT sessions over 14 w” and the research team announced the work on social media: “✨ New publication! We just published a case study on aversion training for release preparation with confiscated Amazona parrots in Costa Rica.”

The Costa Rica case appears to be one of several projects across Latin America that are testing how to rehabilitate parrots seized from the illegal pet trade. Parallel work at the Wild Animals Triage Center (CETAS) of Juiz de Fora, Brazil, has used combined flight and human-aversion training on other Amazona species and provides concrete methods that rehabilitation centers can consider. In the Brazil protocol, flight conditioning was applied four times per week in the afternoon and used a capture net to simulate a capture for five minutes to stimulate sustained flight. Human-aversion conditioning in that project was executed three times per week in the morning: an evaluator offered sunflower seeds, and if a parrot accepted the food the evaluator would shake a can filled with stones to make “a high and disturbing noise to the animal.” Parrots in the Brazil program were tested monthly and the combined program ran for ten weeks.

Behavioral assessments in the Brazilian work highlighted four temperament dimensions relevant to release readiness: activity, neophilia, vigilance, and fearfulness. More fearful parrots showed stronger responses to physical restraint, with more vocalizations and struggle attempts. After training, parrots showed higher responsiveness to physical restraint, and investigators suggested that controlled restraint could be used at rehabilitation centers for routine handling such as blood collection to gather data on individual fear responses.

Acclimatization and soft-release procedures used in Brazil also offer practical models. Birds were housed from March 2021 until November 2021 in release-site aviaries measuring 12 m by 4 m by 3.5 m, placed 2 m apart, furnished with widely spaced perches, and fed in ways that encourage flying. Predator-aversion work paired predator models with an aversive net stimulus. Post-release monitoring recorded a shift away from captive behaviors and toward wild foraging, with some released individuals reproducing; separate project notes reported that 13 individuals survived (~68%) after 12 months of monitoring, though cohort definitions vary across reports.

Several important discrepancies remain between studies: the Costa Rica case lists 12 Yellow‑naped Amazons and a tally of 36 HAT sessions “over 14 w,” while Brazil reports cohorts of 38 and other summaries list 51 birds across species. These differences underline the need for clear, published protocols and full cohort descriptions.

For community caretakers and rehabilitation managers, the practical takeaway is clear: pairing human-aversion conditioning with flight training, temperament assessment, and soft-release infrastructure can reduce the risk that released parrots will approach people. Verify histories, measure flight capacity and temperament, and monitor post-release survival and behavior to build evidence-based release programs. Continued publication of full methods and outcomes will be essential to refine HAT dosing, prioritize release sites, and scale practices across centers.