Lake Retba or Lac Rose as it is commonly known by the locals is an unusual lake in Africa that will surely catch the eye of an unsuspecting tourist because of its color. Found in Senegal, the lake is separated by narrow dunes from the Atlantic Ocean and its salt content is very high compared to other water bodies in the country.
Its pink waters are caused by an algae called Dunaliella salina. The algae produce a red pigment to help them absorb sunlight, which gives them energy to create Adenosine Triphosphate (ATP). The color is particularly visible during the dry season (from November to June) and less visible during the rainy season (July to October).
The lake is known for its high salt content (up to 40% in some areas), which is mainly due to the ingress of seawater and its subsequent evaporation. Like the Dead Sea the lake is sufficiently buoyant that people can float easily. 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.
They protect their skin with beurre de Karité (shea butter), an emollient produced from Shea nuts which helps avoid tissue damage. The salt is used by Senegalese fishermen to preserve fish, which is an ingredient in many traditional recipes, including the national dish, which is a fish and rice combination called thieboudienne. About 38,000 tonnes of salt are harvested from this lake each year, which contributes to Senegal’s salt production industry. Senegal is the number-one producer of salt in Africa.
With a depth of only three meters, each harvester paddles to a chosen area using a long stick to push against the bottom of the lake to feel where the salt is. The boat they rent to collect the salt is called a pirogue and is made of wood. Using any engine or metal fixture would suffer immediate rust.
These harvesters are Malians, Guineans, Ivorians, Burkinabe and even some from Guinea-Bissau all neighboring countries. The men who work as the harvesters, filling their baskets with salt before heaving it over their heads into their boats, can harvest between 10 to 12 buckets. There are others, basically women, who wait onshore, to carry the salt from boat to land.
Not many living organisms are able to survive in Lake Retba because of its high salt content, so it serves mainly as a tourist point and for salt production. In fact, if you decide to visit the lake, you will constantly see salt collectors working at the lake and the shores of Lake Retba are full of piles of collected salt.
Some local experts are worried that the lake’s salt is being overexploited. Although action has been taken to protect it – the government has banned seashell mining and the lake is now given an annual biological rest – there is still a risk that if the environmental situation were to deteriorate, the effects could be quite serious.
Lake Retba is the only pink lake in Africa and It is a top tourist attraction and the salt dug from its bed also underpins the local economy on which thousands of people in Senegal and West Africa depend.
The Pink Lake has been on UNESCO’s tentative heritage list since 2005, but this has still not materialized. However, if environmental protection is not maintained, significant harm could be done to the lake.