The Secret Behind Pink Lake

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 calledDunaliella 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 antioxidantsthat 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

Pink Lake is a salt lake in the Goldfields-Esperance region of Western Australia. It lies about 3 kilometres (2 mi) west of Esperance and is bounded to the East by the South Coast Highway.

The lake is not always pink in colour but the distinctive colour of the water when the lake is pink is a result of the green alga Dunaliella salina, halobacterium Halobacteria cutirubrum, and or high concentration of brine shrimp. Once the lake water reaches a salinity level greater than that of sea water, the temperature is high enough and adequate light conditions are provided, the alga begins to accumulate the red pigment beta carotene. The pink halobacteria grow in the salt crust at the bottom of the lake and the colour of the lake is a result of the balance between D. salina and H. cutirubrum.