Conservation Genetics

, Volume 15, Issue 6, pp 1447–1462 | Cite as

Connectivity and gene flow among Eastern Tiger Salamander (Ambystoma tigrinum) populations in highly modified anthropogenic landscapes

  • Valorie R. TitusEmail author
  • Rayna C. Bell
  • C. Guilherme Becker
  • Kelly R. Zamudio
Research Article


Fragmented landscapes resulting from anthropogenic habitat modification can have significant impacts on dispersal, gene flow, and persistence of wildlife populations. Therefore, quantifying population connectivity across a mosaic of habitats in highly modified landscapes is critical for the development of conservation management plans for threatened populations. Endangered populations of the eastern tiger salamander (Ambystoma tigrinum) in New York and New Jersey are at the northern edge of the species’ range and remaining populations persist in highly developed landscapes in both states. We used landscape genetic approaches to examine regional genetic population structure and potential barriers to migration among remaining populations. Despite the post-glacial demographic processes that have shaped genetic diversity in tiger salamander populations at the northern extent of their range, we found that populations in each state belong to distinct genetic clusters, consistent with the large geographic distance that separates them. We detected overall low genetic diversity and high relatedness within populations, likely due to recent range expansion, isolation, and relatively small population sizes. Nonetheless, landscape connectivity analyses reveal habitat corridors among remaining breeding ponds. Furthermore, molecular estimates of population connectivity among ponds indicate that gene flow still occurs at regional scales. Further fragmentation of remaining habitat will potentially restrict dispersal among breeding ponds, cause the erosion of genetic diversity, and exacerbate already high levels of inbreeding. We recommend the continued management and maintenance of habitat corridors to ensure long-term viability of these endangered populations.


Ambystoma tigrinum Tiger salamander Landscape genetics Fragmentation 



We thank Al Breisch and Dan Rosenblatt of the New York State Department of Environmental Conservation, and Dave Golden of the New Jersey Division of Fish and Wildlife, for support with population sampling and permits. All sample were collected according to approved Brookhaven National Laboratory IACUC #347. This research was funded in part by State Wildlife Grant T-2-2 from the U.S. Fish and Wildlife Service (USFWS) to the New York State Department of Environmental Conservation (NYSDEC), an Upstate Herpetological Association Research Grant to VT, and an NSF Population Evolutionary Processes award to KZ. RCB was supported by a Cornell University Presidential Life Sciences Fellowship and CGB was supported by a Fulbright/CAPES Fellowship.


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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  • Valorie R. Titus
    • 1
    Email author
  • Rayna C. Bell
    • 2
  • C. Guilherme Becker
    • 2
  • Kelly R. Zamudio
    • 2
  1. 1.Natural Resource ManagementGreen Mountain CollegePoultneyUSA
  2. 2.Department of Ecology and Evolutionary BiologyCornell UniversityIthacaUSA

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