Individual study: Released captive-reared female grey partridges Perdix perdix exhibit poor survival and low reproductive success, Arbroath and Kirriemuir, Angus, Scotland
Parish D.M.B. & Sotherton N.W. (2007) The fate of released captive-reared grey partridges Perdix perdix: implications for reintroduction programmes. Wildlife Biology, 13, 140-149
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Release captive-bred individuals into the wild to restore or augment wild populations of gamebirds
A replicated, controlled study in two arable farmland areas in Angus, Scotland, found that, due to poor survival and low reproductive success, releasing commercially reared grey partridges Perdix perdix did not contribute to bolstering declining wild populations (Parish & Sotherton 2007). Studies were conducted at one site in autumn 1997 to summer 2001 and a second in autumn 2001 to summer 2004. Eight-week old commercially-reared partridges were placed in release pens in September each year and released 2-3 weeks later. Released birds (520) were monitored by spring and autumn counts, night-time surveys and radio-telemetry. Some wild female partridges were radio-tagged for comparison. Survival of captive-reared birds from autumn to the following spring was low (averaging 10%). Breeding-season survival of released females averaged 30% and for wild females 44%. The major cause of mortality was predation (69% of losses). Of the few reared birds that survived to breed, none fledged chicks in their first breeding season. Only one released female survived to breed in her second year, but this individual raised 14 young.