Study

Restoration of butterfly populations in Britain

Actions

This study is summarised as evidence for the following.

Action Category

Release captive-bred individuals to the wild

Action Link
Butterfly and Moth Conservation

Translocate to re-establish populations in known or believed former range

Action Link
Butterfly and Moth Conservation
  1. Release captive-bred individuals to the wild

    A review from pre-1900–1988 across the UK and Ireland (Pullin 1996) found that at least a quarter of reintroduced butterfly populations survived for over three years, but only 8% were known to survive for more than 10 years after release. Of 274 documented reintroductions of native butterflies, 68 populations (25%) were known to have survived for more than three years, and 21 (8%) were known to survive for more than 10 years. However, 103 populations (38%) died out within three years of release. The remaining reintroductions were either poorly documented (73 releases) or occurred too recently to determine success (30 releases). Twenty-five releases which aimed to reinforce existing populations are not included. Records of all documented releases of butterflies in the UK and Ireland were compiled by Oates & Warren (1990), and their success up to 10 years after release was updated by this study. At least 29% of releases were of captive-bred butterflies. No further details were provided.

    Oates M.R. & Warren M.S. (1990) A review of butterfly reintroductions in Britain and Ireland. Joint Committee for the Conservation of British Insects/World Wildlife Fund, Godalming, United Kingdom.

    (Summarised by: Andrew Bladon)

  2. Translocate to re-establish populations in known or believed former range

    A review from pre-1900–1988 across the UK and Ireland (Pullin 1996) found that at least a quarter of reintroduced butterfly populations survived for over three years, but only 8% were known to survive for more than 10 years after release. Of 274 documented reintroductions of native butterflies, 68 populations (25%) were known to have survived for more than three years, and 21 (8%) were known to survive for more than 10 years. However, 103 populations (38%) died out within three years of release. The remaining reintroductions were either poorly documented (73 releases) or occurred too recently to determine success (30 releases). Twenty-five releases which aimed to reinforce existing populations were not included. Records of all documented releases of butterflies in the UK and Ireland were compiled by Oates & Warren (1990), and their success up to 10 years after release was updated by this study. At least 29% of releases were of captive-bred butterflies. No further details were provided.

    Oates M.R. & Warren M.S. (1990) A review of butterfly reintroductions in Britain and Ireland. Joint Committee for the Conservation of British Insects/World Wildlife Fund, Godalming, United Kingdom.

    (Summarised by: Andrew Bladon)

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