The renowned pink Lake Hillier in Australia is truly a marvel to witness. It was first spotted by a Royal Navy explorer back in 1802, and its stunning shade resembling a strawberry milkshake is truly breathtaking.
Located near the shore of Middle Island in the Recherche Archipelago, south of Western Australia, is Lake Hillier. The reason behind the lake’s distinct pink color remains a topic of discussion, but it is believed to be related to the microorganisms inhabiting the lake.
Lake Hillier is now a protected pasture reserve that can only be visited under special circumstances, and it is recommended to view it from the air. The reason behind Lake Hillier’s unique bubblegum or strawberry milkshake color is not known for certain, but most scientists believe that it could be due to the presence of a specific species of microalgae called Dunaliella Salina. These photosynthetic microorganisms thrive in high-salt environments and use other parts of the visible light spectrum except for orange/red frequencies to generate energy.
Dunaliella Salina is a tiny organism that has an amazing ability to survive in extremely salty environments, ranging from 0.2% to an impressive 35%. Interestingly, these creatures are known to produce carotenoid pigments, specifically beta-carotene which is also found in carrots. These pigments are believed to be responsible for the striking pink color of the lake water, resembling bubblegum.
The salt crusts of the lake contain a significant amount of halophilic bacteria and archaea which could be responsible for the lake’s fascinating appearance. These microorganisms that are not algae also produce a comparable carotenoid pigment within their cell membranes, which could either be the primary cause or a contributing factor to the overall coloration of the lake. This information was sourced from Viaggio Routard/Flickr.
The ABRF’s Metagenomics Research Group has conducted the Extreme Microbiome Project on a lake using metagenomic analysis. The study discovered several species including Dunalialla, Saliibacter Ruber, Dechloromonas Aromatica, and various Archaea. These hypersaline lakes, like Hillier, are primarily composed of bacteria and archaea, which contribute to the pink color of the water. Lake Retba is another well-known pink lake located on the coast of Senegal and is often used by locals for salt harvesting. It was also the finish line for the Dakar Rally road race.
During the dry season, which falls between November and June, the color of Retba is particularly noticeable. However, during the rainy seasons, it is not as apparent. This information comes from Gordonlgl/Wikimedia Commons.
The microalgae species present in the water is believed to be responsible for giving Lake Hillier its distinctive appearance. This same type of microalgae is widespread in the lake. (Photo credit: Jeff Attaway/Flickr)
The information available suggests that it is safe to swim in Lake Hillier, the famous pink lake of Australia. Although the water is pink in color, it is clear and poses no harm to your skin or health. However, like most bodies of water, there are no macro-organisms like fish to worry about. The algae in the lake are completely harmless but it is not advisable to drink the hypersaline water. Unfortunately, this lake is not easily accessible for regular tourists as it is difficult to get to, making it almost impossible to visit on the ground. However, visitors can enjoy the vibrant pink color of the lake from the air, which offers a breathtaking view of the surrounding forests and the Indian Ocean. Some travelers may be able to get dropped off on Middle Island via helicopter rides or cruise ships, but they usually view the lake from the shore.
In the rare event that you find yourself near the lake and decide to take a swim, you’re in for a unique experience. While it’s now primarily a tourist attraction, Lake Hillier was once used for salt extraction. The British Navigator and Cartographer Mathew Flinders discovered the lake in 1802 while aboard the HMS Investigator. He climbed the highest peak on the island, which is now named after him, and noted in his log that he was surprised to see “a small lake of rose color.” Flinders decided to name the lake Hillier in honor of a crew member who had recently passed away from dysentery while they were docked on the island.
Upon reaching the shore to investigate, the crew discovered that the lake shared similarities with the Dead Sea due to its salty nature. They took advantage and collected salt from the lake’s shores. Captain Flinders’ log revealed a smaller rose-colored lake located in the northeast area of the island, which had an abundance of salt that could crystallize and load a ship. Today, Lake Hillier is an uninhabited pasture reserve filled with dense Eucalyptus forests. It is not recommended to drink water from this lake or any other saltwater body as it can cause harm to the body. Consuming salty water can put a strain on the body’s natural ability to stabilize sodium and chloride levels, leading to cell membrane damage.
When you are in a hypertonic environment, water cannot freely enter your cells. Instead, osmosis occurs and causes water to leave the cell’s interior to correct the concentration imbalance. Consequently, the cells in your body shrink, and your kidneys try to solve the issue by producing urine to remove excess sodium. However, the kidneys can only perform this function if the urine is less salty than saltwater. Otherwise, you may lose more water than you drank, leading to dehydration. To make matters worse, there are numerous microorganisms present in the water. While most of them are harmless, there is a risk of ingesting something unpleasant.