Why do some lakes turn pink?

Across the world, in places from Australia to Africa, there are lakes with an astonishing feature: their water is bright pink, the color of strawberry milk or bubblegum. Seen from above, they look almost unreal, as if someone had spilled paint into the landscape. But this striking color is completely natural, and the science behind it is fascinating.

Pink lakes share one key feature: they are extremely salty. Most pink lakes are what scientists call terminal lakes, meaning water flows in but has no way to flow out. The only way water leaves is by evaporating under the sun. Just as in the Dead Sea, this leaves the salt behind, and over time the water becomes far saltier than the ocean. This intense saltiness creates a very harsh environment where most ordinary life cannot survive.

Although the water is too salty for most living things, a few special organisms thrive in it. These are salt-loving microbes, including a type of algae and certain bacteria. To survive the intense salt and bright sunlight, these tiny organisms produce special protective pigments. These pigments are reddish and pinkish in color. They belong to the same family of natural color compounds, called carotenoids, that make carrots orange.

When huge numbers of these salt-loving microbes fill a salty lake, all their tiny pink and red pigments together turn the entire body of water pink. The color is often strongest in the hottest, driest part of the year, when the water is saltiest and the microbes are most active. So the next time you see a photo of an impossibly pink lake, you are really looking at the work of countless tiny living things, all colored by the pigments that keep them alive.

This article was written using information from Wikipedia.