Lake Enriquillo

Lake Enriquillo (Spanish: Lago Enriquillo) is a hypersaline lake in the Dominican Republic located in the southwestern region of the country. Its waters are shared between the provinces of Bahoruco and Independencia, the latter of which borders Haiti. Lake Enriquillo is the largest lake in both the Dominican Republic and Hispaniola, as well as the entire Caribbean. It is also the lowest point for an island country.

Hydrology

Lake Enriquillo covers an area of , and is the lowest point for an island country, falling below sea level. Its drainage basin includes ten minor river systems. The rivers that rise in the Neiba Mountains to the north (lower center and lower right of the image) are perennial. Those rivers that rise in the Baoruco Mountains to the south are intermittent. Lake Enriquillo has no outlet. The lake's water level varies because of a combination of storm-driven precipitation events and the region's high evaporation rate. Salinity in the lake can vary between 33 parts per thousand (comparable to seawater) and over 100 parts per thousand (hypersaline).

The region has a hot, semiarid climate. Annual rainfall is not evenly distributed, with peak precipitation occurring in May and October. The dry season is December through April when rainfall may be less than . Due to the length of the lake, annual rainfall averages also vary at the eastern and western ends: on the northwest shore, and in the southeast.

Flooding trend

Between 2004 and 2009, the lake doubled its surface area. Records for 2004 show the lake to be ; measurements from 2011 put the area at .

Reasons for the flooding are being debated, but may be a combination of several, including increases in rainfall in the region in recent years, increase of sediments going into the lake from run-off due to deforestation that are contributing to raising the lakebed, and milder temperatures, which are reducing the surface evaporation rate.

Geography

The lake lies in a valley that stretches from near Port-au-Prince in Haiti to Bahia de Neiba in the Dominican Republic. The valley is known as the Hoya de Enriquillo in the Dominican Republic and as the Plain du Cul-de-Sac in Haiti. Parts of the depression are below sea level and are covered by large salt lakes, including Lake Enriquillo and Etang Saumâtre.

There are three islands in the lake: Barbarita, Islita, and Isla Cabritos. Once, when water levels dropped during dry spells, the islands were linked to one another by sandbars. As of December 2011, only Isla Cabritos remains; the other two islands are submerged by the rising level of the lake.

Geology

Lake Enriquillo is located within a linear depression that formed as a ramp basin between the Haiti fold and thrust belt to the north and the uplifted oceanic crust of the Massif de la Selle and Sierra de Bahoruco mountain ranges to the south. The Enriquillo-Plantain Garden fault is a later strike-slip fault, cutting across the depression, which extends from Jamaica in the west, to near Neiba in the Dominican Republic in the east. The valley, a former marine strait, was created around one million years ago when the water level fell and the strait was filled in by sediments of the Yaque del Sur River. Tremors in the region are common.

Ecology

Lake Enriquillo is home to the largest population of American crocodiles (Crocodylus acutus) in the Caribbean. Three species of fish inhabit the lake: the blackbanded limia (Limia melanonotata), the Hispaniolan gambusia (Gambusia hispaniolae), and the Hispaniola pupfish (Cyprinodon bondi). Two endangered iguanas endemic to Hispaniola live sympatrically on Isla Cabritos: the Ricord's iguana (Cyclura ricordii), and the rhinoceros iguana (Cyclura cornuta). The endemic Hispaniola racer (Haitiophis anomalus), a snake, is also native to the area. Among the numerous bird species found at the lake, American flamingos (Phoenicopterus ruber) are prominent; flocks of flamingos are especially concentrated on Isla Cabritos and near the eastern end of the lake.

Plants that thrive in arid places, such as cacti (especially the endemic Melocactus lemairei), can be found here.

A national park was established in 1974 to preserve the area; in 2002 it was combined with two other parks to form the Jaragua-Bahoruco-Enriquillo Biosphere Reserve.

History

The lake is named after Enriquillo, a cacique of the indigenous Taíno, who rebelled against the Spaniards in the early 16th century, and hid in the mountains south of the lake. It was previously called Lake Xaragua, after the Taino chiefdom in which it was located.

External links

• Jaragua-Bahoruco-Enriquillo Reserve, Biosphere Reserve Information at UNESCO, MAB Directory