Lake Hillier is a saline lake located on Middle Island, which is the largest of the islands that make up the Recherche Archipelago in Western Australia.

The lake is famous for its striking pink color, which is a result of a unique combination of natural factors.

The vibrant pink hue of Lake Hillier is primarily attributed to the presence of a microorganism called Dunaliella salina. This microorganism produces a red pigment, known as beta-carotene, which gives the lake its distinctive color. The reason behind the abundance of Dunaliella salina in Lake Hillier is still not fully understood.

The lake’s pink color remains visible even when water from the lake is collected in a container. However, when the water is poured into a different location, such as a glass, it appears more transparent with a slight pink tinge. This phenomenon suggests that the pink coloration is not solely due to the reflection of light off the lake’s surface, but also due to the presence of the pigment within the water.

Despite its unusual appearance, Lake Hillier does not pose any known health risks to humans. The water is safe to swim in, although it is not recommended to do so, as the lake is a protected natural area and access is restricted. Visitors can observe the lake’s unique color from the air by taking helicopter or airplane tours or view it from nearby lookout points.

It’s important to note that information about Lake Hillier is accurate up until September 2021, and any recent changes or developments regarding the lake may not be reflected in this response.