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Providing evidence to improve practice

Individual study: Fostering, hand rearing and releases of yellow-shouldered amazons Amazona barbadensis lead to population increase on an island in Venezuela

Published source details

Sanz V. & Grajal A. (1998) Successful reintroduction of captive-raised yellow-shouldered Amazon parrots on Margarita Island, Venezuela. Conservation Biology, 12, 430-441


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Foster eggs or chicks of parrots with wild conspecifics Bird Conservation

A 1998 review of a yellow-shouldered Amazon Amazona barbadensis release programme on Margarita Island, Venezuela (Sanz & Grajal 1998), found that, of 53 nestlings fostered to wild nests between 1989 and 1996, 44 (83%) chicks eventually fledged. The population on the island increased from 750 to approximately 1900 individuals between 1989 and 1996 as a result of recruitment increasing from zero in 1989 to 53 birds/year following management. This study is discussed in more detail in ‘Release captive-bred individuals’, ‘Artificially incubate or hand-rear birds in captivity’ and ‘Use education programmes and local engagement to help reduce pressures on species’.

 

Artificially incubate and hand-rear parrots in captivity Bird Conservation

A small study in 1990-1 on Margarita Island, Venezuela (Sanz & Grajal 1998), found that all 14 yellow-shouldered amazon Amazona barbadensis chicks hand-reared at a release centre fledged successfully. Two of the birds were killed by predators before release, but the remaining 12 were released and at least ten survived for at least a year (see ‘Release captive-bred individuals’ for details). Hand-rearing involved feeding birds three times a day using a syringe with commercial parrot food and fruits. From 55 days old, chicks were provided with chunks of fruit and whole fruits. This study is also discussed in ‘Foster eggs or chicks with wild conspecifics’ and ‘Use education programmes and local engagement to help reduce pressures on species’.

 

Release captive-bred individuals into the wild to restore or augment wild populations of parrots Bird Conservation

A 1998 before-and-after study, reviewing a yellow-shouldered amazon Amazona barbadensis release programme in semi-dry tropical shrubland on Margarita Island, Venezuela (Sanz & Grajal 1998), found that the population on the island increased from 750 to approximately 1,900 individuals between 1989 and 1996. Conservation measures are also discussed in: ‘Release captive-bred individuals’, ‘Artificially incubate or hand-rear birds in captivity’, ‘Foster eggs or chicks with wild conspecifics and ‘Use education programmes and local engagement to help reduce pressures on species’. For releases, birds were kept in large outdoor aviaries at the release site and released when either 18 or 30 months old. Food was placed outside aviaries twice daily for 15 days after release and once daily for another 15 days. At least ten of 12 birds released survived for at least a year and integrated into wild groups five days to nine months after release. At least three birds scouted nest holes and one nested and fledged two chicks. The programme is estimated to have cost US$2,800 for each bird.

 

Use education programmes and local engagement to help reduce persecution or exploitation of species Bird Conservation

A 1998 review of a yellow-shouldered amazon Amazona barbadensis release programme on Margarita Island, Venezuela (Sanz & Grajal 1998), found that the population on the island increased from 750 to approximately 1,900 individuals between 1989 and 1996. The authors argue that the success was dependent to a large degree on a five-year public education and awareness programme, with promotions such as making the parrot the state bird, visiting local schools, involving youth conservation brigades and local news reports. The details of the reintroduction programme are in ‘Release captive-bred individuals’, ‘Artificially incubate and hand-rear birds in captivity’ and ‘Foster eggs or chicks with wild conspecifics’.