ABC Science‘s Weird Australia looked at the country’s pink lakes and why they’re that colour. The tl;dr answer: a micro-algae called Dunaliella salina and a pinkish-red bacteria called Salinibacter rubber. Dunaliella salina lives in the lakes and produces beta carotene to protect themselves from UV rays, which give vegetables like red cabbage their colour. Salinibacter rubber is already pinkish in colour and is more abundant in lakes such as Lake Hillier which features in the above video.
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