Background information and definitions
Translocations, also known as relocations, reintroductions, restocking, or repatriations, involve the intentional release of captive-bred and/or wild-caught birds into the wild in order to re-establish a population that has been lost, or augment a critically small population. This can reduce the risk of inbreeding, or simply increase the range of a species and therefore the maximum possible population. Translocations are also frequently used to move birds to areas that have been cleared of invasive predators, particularly on islands. This intervention is not the same as that of periodically moving next boxes to prevent predators from learning their locations, discussed in ‘Invasive and other problematic species’.
Translocations are typically expensive and may risk spreading pathogens to previously unexposed areas.
Supporting evidence from individual studies
A review of two years (1987 and 1993) of survey data from 239 bird translocations in North America and Australasia (Wolf et al. 1996) showed 63% of 134 translocations in 1987 and 67% of 105 in 1993 resulted in the establishment of self-sustaining populations. Those translocations involving larger numbers of individuals, translocations of native game species (rather than threatened species), and translocations into the core (rather than the periphery) of the species’ historical range were most likely to establish self-sustaining populations.Study and other actions tested