Conservation Genetics

, Volume 16, Issue 1, pp 125–135 | Cite as

The relationship between distance and genetic similarity among invasive rat populations in the Falkland Islands

  • Michael A. Tabak
  • Sally Poncet
  • Ken Passfield
  • Matthew D. Carling
  • Carlos Martinez del Rio
Research Article


Norway rats (Rattus norvegicus) have been either introduced to or have invaded a large number of the world’s islands. Rats have caused population declines and the extinction of island endemics. Their eradication is often a major conservation success as it leads to recovery of affected species and even ecosystem processes. However, eradication efforts can be hampered by the ability of rats to re-colonize eradicated islands. Here we present the results of genetic analyses that inform migration rates and population structure of Norway rats from 14 sampling locations in the Falkland Islands, where rat eradication efforts are taking place. We used 12 microsatellite markers and population genetic tools to estimate rat migration patterns between 12 islands that were separated by distances ranging from 230 m to 112 km. We found evidence of significant migration rates, and hence presumably of rat movements between islands up to 830 m away from each other. Norway rats seem capable of swimming this distance even in the cold waters of the Falkland Islands. Our results can inform managers about strategies of rat eradication in the Falklands including minimal distances that reduce recolonization and the choice of island clusters for eradication.


Invasive species Islands Eradication Rattus norvegicus Microsatellites 



This project was partially funded by the Shackleton Scholarship Fund, Antarctic Research Trust, Wyoming Biodiversity Institute, and NSF Grant #0841298. We wish to thank Nick Rendell, Environmental Planning Officer for the Falkland Islands Government, for his assistance with permits for this research. We also thank Tony and Susan Hirtle, Mike and Phyll Rendell, and Steven Dickson for permission to access sampling locations, and to Derek Brown for his advice and insights. The comments of Liz Mandeville and two anonymous reviewers benefitted previous versions of this manuscript.

Supplementary material

10592_2014_646_MOESM1_ESM.docx (28 kb)
Supplementary material 1 (DOCX 28 kb)
10592_2014_646_MOESM2_ESM.xlsx (18 kb)
Supplementary material 2 (XLSX 18 kb)


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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  • Michael A. Tabak
    • 1
    • 2
  • Sally Poncet
    • 3
  • Ken Passfield
    • 3
  • Matthew D. Carling
    • 1
    • 2
  • Carlos Martinez del Rio
    • 1
    • 2
    • 4
  1. 1.Department of Zoology and PhysiologyUniversity of WyomingLaramieUSA
  2. 2.Program in EcologyUniversity of WyomingLaramieUSA
  3. 3.Beaver Island LandCareStanleyFalkland Islands
  4. 4.Wyoming Biodiversity InstituteUniversity of WyomingLaramieUSA

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