Saint Croix ground lizard  (Ameiva polops)

The main reasons for the disappearance of the Saint Croix ground lizard on Saint Croix Island are habitat loss and the introduction of a mammalian predator, the Indian mongoose (Herpestes auropunctatus), both of which continue to threaten the future of the species in its remaining range (2). There is evidence that the decline on Saint Croix Island correlates with the introduction of the Indian mongoose in 1884 (2). The accidental introduction of the mongoose onto Green, Protestant or Ruth Cay could be catastrophic, most likely resulting in the extinction of the species (7).

Extensive development of coastal areas probably also contributed to the disappearance of this lizard on Saint Croix (2), and poses a significant threat to remaining populations. Suitable habitat is rapidly diminishing on Protestant Cay due to landscaping practices by hotel management, including activities such as raking, removal of leaf litter and undergrowth, and planting of exotic vegetation (8). A second concern is the vulnerability of the Saint Croix ground lizard to natural disasters such as hurricanes that strike the islands of both Green and Protestant Cay (2).

With such small, isolated populations, the Saint Croix ground lizard now faces the additional threat of reduced genetic variation through inbreeding, which would make it more vulnerable to natural disasters or disease as well as having a negative impact on fertility (7).

Green Cay was established as a National Wildlife Refuge in 1977 by the U.S. Fish and Wildlife Service to protect the largest remaining population of the Saint Croix ground lizard. This refuge protects 14 out of the 18 acres of designated critical habitat on Green Cay, which is closed to the public, keeping human disturbance to a minimum (7).

Recently, a cooperative agreement has been drawn up between the U.S. Fish and Wildlife Service and a private hotel (Hotel on the Cay) on Protestant Cay for the conservation and management of this endangered lizard. Efforts have included the recruitment of students from a range of middle and high schools to help restore and maintain the lizard's habitat on the island (3).

Ruth Island was not created to protect this lizard, but ten individuals were translocated there in 1990 for this purpose. Recent population estimates suggest that the population has grown to become the second largest for this species, around 60 individuals, and such increases are extremely encouraging (4). With this success, the reintroduction of a recommended 50 lizards on to Buck Island has been planned, now that a mongoose eradication programme has been carried out on the island (3). This hardy species appears to be capable of thriving on mongoose-free islands if habitat remains relatively undisturbed (3). Thus its release on Buck Island will help reignite hope for the future survival of this tiny lizard.