Lake Natron, nestled in northern Tanzania, is a natural wonder known for its visually striking, often blood-red waters. This shallow soda lake has gained a reputation for its unusual properties, particularly its perceived ability to “turn animals into stone.” The lake’s unique and dangerous characteristics stem from a combination of extreme environmental factors that create an inhospitable yet captivating landscape.
The Lake’s Extreme Chemistry
The lake’s hazardous nature is rooted in its distinct chemical and physical composition. The lake exhibits exceptionally high alkalinity, with pH levels frequently exceeding 10 and sometimes reaching over 12, comparable to household bleach or ammonia. This extreme pH is primarily due to high concentrations of evaporite minerals, such as sodium carbonate and trona, which accumulate as water evaporates. The lake’s temperatures can be scorching, often exceeding 40°C (104°F) and sometimes reaching up to 60°C (140°F). These conditions create a caustic and corrosive environment. The geological origins of these unique mineral deposits are linked to the nearby Ol Doinyo Lengai volcano, an active stratovolcano that erupts a rare type of lava rich in sodium and potassium carbonates. Volcanic ash and materials from the volcano, along with mineral-rich hot springs, contribute to the lake’s high alkalinity and the deposition of natron and trona into its waters.
Impact on Wildlife
The extreme chemical conditions of Lake Natron affect animals that come into contact with its waters. Many creatures that perish in the lake undergo a process often described as “petrification,” where their bodies are preserved in a mummified, stone-like state. This phenomenon occurs because the high levels of sodium carbonate and other minerals in the water effectively dry out and encrust the carcasses, preventing decay and leading to calcification. The corrosive nature of the water can cause severe chemical burns and damage soft tissues of animals that attempt to drink or wade in it. Animals are not instantly turned to stone upon contact, but rather, their remains are preserved by the lake’s unique chemistry after they die, creating intact figures along the shoreline.
Human Safety and Precautions
Lake Natron also poses direct dangers to humans. Direct contact with the highly alkaline water can cause severe chemical burns to the skin and eyes, and ingestion can be fatal. Visitors are advised to avoid touching the water and to maintain a safe distance. Necessary precautions for those near the lake include wearing protective footwear, as the ground can be hot and sharp with salt crystals, and eye protection. The air around the lake can also contain ammonia, which, if inhaled, can harm the eyes, throat, and lungs.
Life Thrives in Extremes
Despite its hostile environment, Lake Natron supports a unique ecosystem of specialized life forms. Extremophile microorganisms, particularly salt-loving algae (halophilic microorganisms) and cyanobacteria, thrive in the lake’s highly saline and alkaline conditions. These microorganisms produce red pigments, giving the lake its red and pink hues. These algae serve as the primary food source for the Lesser Flamingo ( _Phoeniconaias minor_ ), which uses Lake Natron as its main breeding ground in East Africa. The flamingos are uniquely adapted to survive the lake’s harsh conditions, possessing tough skin and scales on their legs to prevent burns and specialized glands in their heads to filter out excess salt. The lake’s caustic nature also deters most predators, providing a safe haven for flamingo nesting.