Lac Rose (meaning Pink Lake) lies north of the Cap Vert peninsula of Senegal, some 30 km (18 miles) north-east of the capital, Dakar, in northwest Africa.
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.
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.
The color is particularly visible during the dry season (from November to June) and is less visible during the rainy season (July to October).
According to en.wikipedia