The water in Senegal's Lake Retba always seems to have a pinkish hue to it. However, catch it during the dry summer months when the saline levels are high and you will see it turn strawberry pink and sometimes, even red. The good news is that color is not the result of chemicals being dumped in the lake but nature, working its magical tricks!
Located in the Cape Vert Peninsula that lies north east of Senegal's capital Dakar, the lake's unusual appearance is caused by a salt-loving green micro alga called Dunaliella Salina that resides in the lake, known for its high concentration of the mineral.
As you can imagine, very few organisms can survive in such highly saline conditions. The only reason this single-celled organism is able to do so, is because of its ability to create large amounts of Beta-Carotene, that helps protect it against the intense light that reflects off the salt and also gives the algae its dark pink hue.
While the color may make the lake appear eerie and unsafe, the micro organism is safe not only to swim amidst, but also, consume - Good news for the locals that are constantly wading in to mine the salt. In fact, the algae are so rich in antioxidants that they are often harvested and used in cosmetics and dietary supplements.
This is not the only tiny organism able to transform water hues. In San Diego,CA and many other parts of the world, high concentrations of phytoplankton during certain time of the year, help turn the ocean waters a bright red during the day and an even cooler bioluminescent blue, at night!
Resources:amusingplanet.com, dailymail.co.uk