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)

Output references
What Works 2021 cover

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 21

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.


Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape ProgrammeRed List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Mauritian Wildlife Supporting Conservation Leaders
Sustainability Dashboard National Biodiversity Network Frog Life The international journey of Conservation - Oryx Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered species Vincet Wildlife Trust