title: Reproductive parameters in the critically endangered Blue-throated Macaw: limits to the recovery of a parrot under intensive management.
abstract: Rediscovered in the wild twenty years ago, the breeding biology of wild Blue-throated Macaws remains largely unexplored, yet is essential to its effective conservation and recovery. Here, we analyse reproductive parameters in an intensively managed wild population of Blue-throated Macaws, providing the first data on the breeding biology of this critically endangered species. During the six-year study period, 2007-2012, the number of active breeding pairs either remained constant or decreased, depending on the site, and no new breeding pairs were discovered despite extensive searching. We documented nesting attempts in natural cavities in dead palms or live hardwoods, and artificial nest boxes. Egg-laying was concentrated during the end of dry season and the beginning of the wet season, August through December. Hatching failure was the greatest cause of egg losses. Half of the breeding attempts of Blue-throated Macaws produced at least one fledging, on average two, after a 85 days nestling period. An average of 4.3 nestlings per year fledged from all known wild nests combined. Each pair lost roughly 65% of its initial reproductive investment at each nesting attempt. In most successful nesting attempts of individualized pairs, a new nesting attempt was not detected the following year. All monitored breeding pairs showed high nest site fidelity, reusing hardwood-tree cavities and nest boxes. Our findings will aid conservation efforts by refining current actions and prompting new approaches towards the conservation and recovery of the Blue-throated Macaw.
authors.affiliation: Instituto Multidisciplinario sobre Ecosistemas y Desarrollo Sustentable, Universidad Nacional del Centro de la Provincia de Buenos Aires, Tandil, Buenos Aires, Argentina; Proyecto de Conservación de la Paraba Barba Azul, The World Parrot Trust, Sachojere, Beni, Bolivia.
authors.forename: Igor
authors.initials: I
authors.lastname: Berkunsky
authors.affiliation: Proyecto de Conservación de la Paraba Barba Azul, The World Parrot Trust, Sachojere, Beni, Bolivia.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Daniele
authors.affiliation: Instituto Multidisciplinario sobre Ecosistemas y Desarrollo Sustentable, Universidad Nacional del Centro de la Provincia de Buenos Aires, Tandil, Buenos Aires, Argentina; Proyecto de Conservación de la Paraba Barba Azul, The World Parrot Trust, Sachojere, Beni, Bolivia; División Zoología de Vertebrados del Museo de La Plata, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina.
authors.forename: Federico P
authors.initials: FP
authors.lastname: Kacoliris
authors.affiliation: Proyecto de Conservación de la Paraba Barba Azul, The World Parrot Trust, Sachojere, Beni, Bolivia; The World Parrot Trust, Lake Alfred, Florida, United States of America.
authors.forename: José A
authors.initials: JA
authors.lastname: Díaz-Luque
authors.affiliation: Proyecto de Conservación de la Paraba Barba Azul, The World Parrot Trust, Sachojere, Beni, Bolivia; Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile.
authors.forename: Carmen P
authors.initials: CP
authors.lastname: Silva Frias
authors.affiliation: División Zoología de Vertebrados del Museo de La Plata, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina.
authors.forename: Rosana M
authors.initials: RM
authors.lastname: Aramburu
authors.affiliation: The World Parrot Trust, Lake Alfred, Florida, United States of America.
authors.forename: James D
authors.initials: JD
authors.lastname: Gilardi
mesh_terms: D000818:Animals; D001838:Bolivia; D001947:Breeding; D052284:Clutch Size; D003247:Conservation of Natural Resources; D056727:Endangered Species; D005843:Geography; D009425:Nesting Behavior; D010311:Parrots / Q000502:physiology*; D010858:Pigmentation; D012098:Reproduction; D012621:Seasons