Lesser Antilles Mangroves

The Lesser Antilles mangrove ecoregion comprises the coastal margins of a chain of islands at the southeastern edge of the Caribbean Sea, from Sombrero and Anguilla in the north to Grenada in the south.

The smaller islands of the Lesser Antilles have fewer species diversity than the larger islands of the Greater Antilles but have high endemism. They also have many habitats associated with environmental conditions related to differences in climate, elevation, rainfall, and salinity found in the different islands.

The total area of mangrove cover on the Lesser Antilles is estimated at 20,636 ha (51,000 acres), distributed among 263 sites. The largest mangrove areas are in Antigua and Barbuda, Guadeloupe, Martinique, and the U.S. Virgin Islands.

Ten different types of mangrove communities have been identified, depending on the dominant mangrove species and whether they occur in estuarine areas, as fringe on an open coast, in depressions or basins, or as scrub vegetation.

The Lesser Antilles mangroves are also found in association with other types of habitats as part of broader coastal wetland systems, with conditions that range from freshwater and brackish to hypersaline, and associated with marshes, swamp forest, coastal woodland, and dunes, and influenced by both land drainage and tidal flushing.

Overall, biodiversity is higher on the larger islands in the southern part of the chain. Still, endemism is more significant in the northern islands that are more isolated from the mainland.

Flora and Fauna

Five mangrove species are found in this ecoregion, including Rhizopora mangle, Avicennia germinans, A. Schaueriana, Laguncularia racemosa, and Conocarpus erectus. Rhizopora mangle and Laguncularia racemosa appear to be the most abundant in all mangrove communities: riverine, basin and fringe.

Other plant species found in the Lesser Antilles mangrove ecoregion communities include Acrostichum aureum, Thespesia populnea, Dalbergia ecastaphyllum, Hibiscus tiliaceus, Pluchea odorata, Anona glabra, Brachypteris ovata, Sporobolus virginicus, and Sporobulus indicus, Mariscus planifrons, Fimbristylis dichotoma, Rhabdenis biflora, Cydista aequinoctialis, and Eichhornia crassipes.

Birds most associated with mangroves include spotted sandpiper (Actitis macularia), great blue heron (Ardea herodias), cattle egret (Bubulcus ibis), green heron (Butorides striatus), belted kingfisher (Ceryle alcyon), Lesser Antillean pewee (Contopus latirostris), West-Indian whistling duck (Dendrocygna arborea), and Lesser Antillean bullfinch (Loxigilla noctis).

Mammals such as West Indian manatee (Trichecus manatus) utilize mangroves. The calving grounds of the humpback whales (Megaptera novaeangliae) are in the Grenadines and between Antigua and Anguilla.

Reptiles of interest are Caiman crocodilus, several species of Anolis lizard (Anolis spp.), iguana (Iguana iguana), Boa constrictor, loggerhead turtle (Caretta caretta), green turtle (Chelonia mydas), olive ridley (Lepidochelys olivacea), and hawksbill turtle (Eretmochelys imbricata).

_{Map depicting the location of the Lesser Antilles mangroves (coastal margins of the islands in the blue box)}