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Translocation to areas free of exotic predators, habitat degradation, or disease may be the most viable restoration option for many endangered species. We report on a successful translocation of the critically endangered St. Croix ground lizard, Ameiva polops, extirpated from St. Croix, U.S. Virgin Islands, Caribbean, by predation from introduced mongooses (Herpestes auropunctatus). We translocated 57 adult A. polops from Green Cay to Buck Island in May 2008. We placed 4 females and 3 males each in eight, 100 m 2 , enclosures on Buck Island for 71 days, then the enclosures were opened. During the enclosure period, 20 individuals were identified and 32 others were seen. The average number sighted per survey was only 5.28 (range = 2–10). One hatchling was sighted in an enclosure, indicating a translocated female successfully nested. Body condition of the translocated individuals increased significantly by the end of the enclosure period. Population monitoring surveys at 61 sites across Buck Island showed that 5 years after the initial translocation in June 2013, the new population had grown to an estimated 1,473 individuals and occupied 58.9% of the island. We attribute eradication of mongoose, life history of the species, large propagule size, condition of habitat, soft-release, use of adults, interagency collaboration, and systematic assessment as primary factors that facilitated this successful translocation. Our findings provide meaningful insights on factors that enhance the potential for successful translocations, and point to new strategies aimed at restoring populations of endangered reptiles in their native ranges.

The Puerto Rican ground lizard (Ameiva exsul) was first documented on St. Croix, U.S. Virgin Islands in 2006. The species is native to Puerto Rico, the northern U.S. Virgin Islands, and the British Virgin Islands, and was purportedly transported to St. Croix with a shipment of goods. Ameiva exsul has since become established in a north- central neighborhood of St. Croix, from which we collected six specimens. Analyses of their gastrointestinal tracts demonstrated they had consumed vertebrates and invertebrates. In particular we documented a Sphaerodactylus sp. gecko, and eggs of the endemic anole, Anolis acutus, as prey of A. exsul. The potential for establishment of A. exsul on offshore cays where the only populations of the St. Croix ground lizard (Ameiva polops) exist is a serious conservation concern, as it may prey on and compete for resources with this critically endangered endemic species.

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.

We report the development of nine polymorphic microsatellite loci for the critically endangered St. Croix ground lizard Ameiva polops. These loci will be useful to determine the genetic health of extant populations of this lizard and their levels of genetic differentiation.

The phylogenetic position of the critically endangered Saint Croix ground lizard Ameiva polops is presently unknown and several hypotheses have been proposed. We investigated the phylogenetic position of this species using molecular phylogenetic methods. We obtained sequences of DNA fragments of the mitochondrial ribosomal genes 12S rDNA and 16S rDNA for this species. We aligned these sequences with published sequences of other Ameiva species, which include most of the Ameiva species from the West Indies, three Ameiva species from Central America and South America, and one from the teiid lizard Tupinambis teguixin, which was used as outgroup. We conducted Maximum Likelihood and Bayesian phylogenetic analyses. The phylogenetic reconstructions among the different methods were very similar, supporting the monophyly of West Indian Ameiva and showing within this lineage, a basal polytomy of four clades that are separated geographically. Ameiva polops grouped in a cluster that included the other two Ameiva species found in the Puerto Rican Bank: A. wetmorei and A. exsul. A sister relationship between A. polops and A. wetmorei is suggested by our analyses. We compare our results with a previous study on molecular systematics of West Indian Ameiva.