Release captive-bred individuals into the wild to restore or augment wild populations of pigeons
Overall effectiveness category Unknown effectiveness (limited evidence)
Number of studies: 1
Background information and definitions
Captive breeding is normally used to provide individuals which can then be released into the wild to either restore a population in part of the speciesâ€™ former range, or to augment an existing population.
Release techniques vary considerably, from â€˜hard releasesâ€™ involving the simple release of individuals into the wild to â€˜soft releasesâ€™ which involve a variety of adaptation and acclimatisation techniques before release or post-release feeding and care. The following section includes studies describing the overall effects of release projects. Studies that compare specific release techniques are described elsewhere (â€˜Use holding pens at release sitesâ€™, â€˜Use â€˜anti-predator trainingâ€™ to improve survival after releaseâ€™ etc).
Supporting evidence from individual studies
A review of a pink pigeon Nesoenas mayeri (formerly Columba mayeri) release programme in mixed forest habitats at Black River Gorges in southern Mauritius between 1987 and 1992 (Jones et al. 1992) found that 36% of 42 pigeons were known to be alive one year after release. This study is also discussed in â€˜Provide supplementary food to increase adult survivalâ€™, â€˜Use captive breeding to increase or maintain populationsâ€™, â€˜Provide supplementary food after releaseâ€™ and â€˜Predator control on islandsâ€™.Study and other actions tested