The regionally endangered Least Grebe (Tachybaptus dominicus) has nested on the three main islands (St. Croix, St. John, St. Thomas) on the United States Virgin Islands (USVI) since 2002. Single pairs (occasionally two pairs) have been confirmed nesting at five man-made freshwater ponds and two salt ponds on St. Croix, at five freshwater ponds on St. Thomas, and at one freshwater pond on St. John. Breeding occurred at six of seven sites on St. Croix from 2004 into 2007 after average, or above-average annual rainfall including torrential rainfall from four autumnal storms (November 2003, September 2004, October 2005, October 2006) that filled freshwater ponds and salt ponds. Least Grebes respond rapidly to water level changes at semi-permanent wetlands and can breed year-round; one pair attempted to nest at least 20 times (eight successfully) at Windsor North Pond on St. Croix. Non-breeding birds in the USVI have occurred less frequently at other freshwater ponds and a few brackish salt ponds, where they also have a restricted distribution. Least Grebe populations in the USVI, at the eastern edge of their breeding range in the Greater Antilles, are generally low. Breeding at man-made freshwater ponds has probably been overlooked in the USVI until recently because of insufficient sampling effort. Future surveys should focus on selected manmade freshwater ponds and brackish salt ponds when water levels are adequate, especially on St. John where birds may have been underreported at salt ponds because of insufficient sampling effort.