Prioritising islands in the United Kingdom and crown dependencies for the eradication of invasive alien vertebrates and rodent biosecurity

  • Andrew StanburyEmail author
  • Sophie Thomas
  • James Aegerter
  • Andy Brown
  • David Bullock
  • Mark Eaton
  • Leigh Lock
  • Richard Luxmoore
  • Sugoto Roy
  • Stan Whitaker
  • Steffen Oppel
Original Article


Invasive alien vertebrates (IAVs) pose a significant threat to island biodiversity worldwide, and their removal is an important nature conservation management goal. As methods advance, eradications from larger islands and of multiple species simultaneously are increasingly undertaken. Effective targeting to maximise conservation gain is important given limited resources. We build on existing prioritisation methods and use the islands of the UK and Crown Dependencies (UK) as an example of how vertebrate eradications might be prioritised and invasive-free status maintained through biosecurity. For each of the 9688 UK islands, we assessed ecological importance for native vertebrates and the anticipated impacts of the IAVs present to estimate the benefit of restoration based on the feasibility and sustainability of IAV eradications in relation to island size, human population and risk of unassisted reinvasion by swimming. As reinvasion poses a threat to the long-term benefits of eradication, we incorporated species-specific swimming distances and explored the effects of varying reinvasion probability from risk-averse to higher-risk strategies. The 25 islands that would benefit most from eradications were in Scotland, Northern Ireland and the Channel Islands. Our prioritisation method should be seen as an initial guide to identify islands that might benefit from intervention when faced with a large list of potential sites. Feasibility studies taking account of factors such as interspecific interactions, anthropogenic reinvasion, views of residents or ‘social feasibility’ and cost need to be undertaken before planning any eradication. We prioritised biosecurity for rat-free islands to highlight where comprehensive measures might be most beneficial.


Invasive alien vertebrate Eradication Island restoration Prioritisation Natural reinvasion risk Rodent biosecurity 



The authors would like to acknowledge everyone who helped construct the benefit and IAV databases; from those carrying out surveys, submitting ad hoc records, writing ecological atlases or working on national recording schemes to local experts providing information directly to the project. J. Russell, J. Millett, N. Holmes and J. Dawson provided valuable advice at different stages of the project.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  • Andrew Stanbury
    • 1
    Email author
  • Sophie Thomas
    • 1
  • James Aegerter
    • 2
  • Andy Brown
    • 3
  • David Bullock
    • 4
  • Mark Eaton
    • 1
  • Leigh Lock
    • 1
  • Richard Luxmoore
    • 5
  • Sugoto Roy
    • 6
  • Stan Whitaker
    • 7
  • Steffen Oppel
    • 1
  1. 1.RSPB Centre for Conservation Science, Royal Society for the Protection of Birds, The LodgeSandyUK
  2. 2.National Wildlife Management Centre, Animal and Plant Health AgencySand HuttonUK
  3. 3.Natural England, Unex HousePeterboroughUK
  4. 4.National Trust, HeelisSwindonUK
  5. 5.The National Trust for Scotland, Hermiston QuayEdinburghUK
  6. 6.IUCNGlandSwitzerland
  7. 7.Scottish Natural Heritage, Great Glen HouseInvernessUK

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