Mongoose Invader: Lizard's Last Stand on St. Croix

In 1884, small Indian mongooses were introduced to St. Croix to address a rat problem in sugarcane fields. This introduction, however, led to a significant decline in the island's native lizard population. The St. Croix ground lizard has vanished from almost 99.97% of its historic habitat, a loss attributed to both habitat destruction for farming and predation by mongooses.

By 1920, lizards had disappeared from the eastern part of St. Croix, with the last sightings on the main island occurring in 1969. The St. Croix racer snake, an endemic reptile, is also considered extinct. Fortunately, lizard populations survived on small, mongoose-free offshore islands like Protestant Cay and Green Cay.

Scientists have since introduced lizards to Ruth Island and Buck Island, with over 3,000 lizards now surviving across these four islands. Recognizing that St. Croix's forests have regrown and its habitat is statistically similar to 1750 conditions, reintroduction to the main island is now being pursued.

In March 2022, experimental lizard populations were released in enclosures at the University of the Virgin Islands wetlands and Sandy Point National Wildlife Refuge. These populations will be closely monitored as efforts continue to potentially re-establish the native lizard on its ancestral home.