The value of behavioral activity records for conservation breeding: the case of Spix’s macaw in human care

The Spix’s macaw ( Cyanopsitta spixii ), extinct in the wild since 2019, is currently maintained in ex situ breeding facilities. Captive breeding expanded the global population from 53 individuals in 2000 to ca. 400 by December 2025, enabling two soft releases. To support reintroduction, we developed an ethogram of 85 behaviors and 1357 quantitative records based on the observation of 123 birds in the facility ACTP Germany, recorded the time activity patterns of ten pairs, and analyzed their breeding output. We tested whether behavioral compatibility—measured here as time-activity synchrony—should complement genetic criteria to improve breeding output. Individual activity patterns were consistent, but females were markedly more synchronized with their mates than with other males. However, a synchrony threshold of at least 75% seemed necessary for successful breeding. Adjusting pair matching based on synchrony and improving general husbandry conditions (diet & enrichment) led to higher breeding output: pairs raising chicks increased from 0 in 2019 to 16 in 2024, fertility rates increased from 39% in 2019 to 60% in 2024, and annual chick output increased from 11 to 44 between 2019 and 2024. These results, based on 86 forced mating attempts, champion the idea that systematic behavioral monitoring can substantially enhance conservation breeding in monogamous parrot species.