Conservation Genetics

, Volume 13, Issue 3, pp 665–679 | Cite as

Conservation genetics of the Critically Endangered Saint Croix ground lizard (Ameiva polops Cope 1863)

  • Luis A. Hurtado
  • Carlos A. Santamaria
  • Lee A. Fitzgerald
Research Article


The Saint Croix ground lizard (Ameiva polops) is a Critically Endangered species endemic to Saint Croix, U.S. Virgin Islands. Although it is completely extirpated from Saint Croix Island (last seen in 1968), two small natural satellite populations survive on two islets off St. Croix: one on Protestant Cay (estimated at ~30 individuals in 2002); and one on Green Cay (estimated at ~180 individuals in 2002). Two additional small populations exist that were founded with individuals translocated from the two surviving natural populations. One is on Ruth Island, a man-made islet off St. Croix, founded in 1990 with 10 individuals from Protestant Cay. The other is on Buck Island, ~2.5 km from Saint Croix, founded in 2008 with 57 individuals from Green Cay. All populations are vulnerable to catastrophic events such as hurricanes, sea level rise, introduction of exotic species, and landscape transformation. Herein, we used mitochondrial and nuclear-microsatellite markers to examine levels of genetic diversity within extant populations of A. polops and the degree of genetic differentiation among them. We also conducted analyses to search for signatures of recent bottlenecks in these populations and to estimate their effective population size (N e ). We found low genetic variability within populations of this lizard, comparable to that observed in other threatened vertebrates. We also found significant genetic differentiation among the three populations examined, as well as signatures of recent bottlenecks and critically low N e values in all populations. Based on our results, we suggest two different conservation units for A. polops: (1) Green Cay and its replicate population at Buck Island; and (2) Protestant Cay and its replicate population at Ruth Island. We discuss the implications of our findings on the conservation and management of A. polops.


Ne estimators comparison Translocations Null alleles HWE deviations Caribbean Teiidae 



Funding was provided by the U.S. National Park Service (USNPS), U.S. Fish and Wildlife Service (USFWS), the U.S. Virgin Island Department of Planning and Natural Resources (USVIDPNR), and the National Science Foundation (grants DEB0743782 to LH; DGE 0654377 to LAF). We especially thank Toby Hibbitts, Daniel Leavitt, Amanda Subalusky, and Mike Treglia for assistance capturing lizards and other critical fieldwork. We also thank Zandy Hillis-Starr (USNPS) and other members of the Ameiva Working Group. In particular we thank Renata Platenberg (USVIDPNR), Jennifer Valiulis (formerly USVIDPNR), Claudia Lombard (USFWS), Michael Evans (USFWS) and Beverly Yoshioka (USFWS Coastal Program). Kimberly Kackley and Desiree Mosley assisted in the laboratory. Mike Treglia kindly provided the map of Saint Croix used in Fig. 1. Mariana Mateos provided comments on the manuscript. Work approved by the Institutional Animal Care and Use Committee, TAMU (AUP #2007-191). Collecting permits provided by USVIDPNR (STX-01808) and USNPS (BUIS-2007-SCI-0011). This is Contribution 203 of the Center for Biosystematics and Biodiversity and contribution 1419 of the Texas Cooperative Wildlife Collection, Texas A&M University.


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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • Luis A. Hurtado
    • 1
  • Carlos A. Santamaria
    • 1
  • Lee A. Fitzgerald
    • 1
  1. 1.Department of Wildlife and Fisheries SciencesTexas A&M UniversityCollege StationUSA

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