Lake Retba

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Lake Retba
LacRose1.jpg
Boats on the lake
Location Cap Vert peninsula
Coordinates 14°50′18.02″N 17°14′41.36″W / 14.8383389°N 17.2448222°W / 14.8383389; -17.2448222Coordinates: 14°50′18.02″N 17°14′41.36″W / 14.8383389°N 17.2448222°W / 14.8383389; -17.2448222
Type saline lake
Basin countries Senegal
Surface area 3 km2 (1 sq mi)
Max. depth 3 metres (9.8 ft)
Cap Vert peninsula / Dakar NASA Image Science and Analysis Laboratory, NASA-Johnson Space Center. 22 Nov. 2004.
Lac Rose in Senegal

Lake Retba or Lac Rose (meaning Pink lake) lies north of the Cap Vert peninsula of Senegal, some 30km (18 miles) north-east of the capital, Dakar[1] in northwest Africa.[2] It is named for its pink waters caused by Dunaliella salina algae and is known for its high salt content, up to 40% in some areas.

Description[edit]

The lake is separated from the Atlantic Ocean only by a narrow corridor of dunes, and is named for its pink waters, caused by Dunaliella salina algae. The algae produces a red pigment to assist in absorbing light, which provides energy to create ATP.[3] The color is particularly visible during the dry season (from November to June) and is less visible during the rainy season (July to October).[4]

Magenta coloured samphire bushes flourish in the white sandbanks, and the sand dunes are terra-cotta-coloured.

Salt[edit]

The lake is known for its high salt content, up to 40% in some areas, which is mainly due to ingress of seawater and its subsequent evaporation.[3] Like the Dead Sea the lake is sufficiently buoyant that people can float easily. [1][5][6]

Salt use[edit]

Salt is exported across the region by up to 3,000 collectors, men and women from all over Western Africa, who work 6–7 hours a day, and protect their skin with "Beurre de Karité" (shea butter, produced from Shea nuts, which is an emollient used to avoid tissue damage. The salt is used by Senegalese fishermen to preserve fish, a component of many traditional recipes including the national dish, a fish stew called thieboudienne.[7][1]

Fish adaptation[edit]

Fish have adapted to the high salt content of the lake, having evolved ways to pump out extra salt and keep their water levels balanced.[8] The fish are approximately four times smaller than when living in a normal environment - this is known as salt water fish dwarfism.[9]

World heritage[edit]

Lake Retba is under consideration by Unesco as a World Heritage Site.[10]

Dakar Rally[edit]

The lake was often the finishing point of the Dakar Rally, before it moved to South America in 2009.[11]

See also[edit]

References[edit]

External links[edit]