Tanzania's Lake Natron is so alkaline that it kills and eerily preserves whatever it touches.
Tanzania's Lake Natron takes its name from the naturally occurring mix of chemicals it contains: mainly sodium carbonate decahydrate (soda ash) and sodium bicarbonate (baking soda). The lake is fed by mineral hot springs and a river, but no water flows out except through evaporation.
As a result, the caustic waters create deadly outcomes.
It may look like this bird was gripped by the icy hand of death, but scientists will explain that it was actually calcified in the caustic waters of Tanzania's Lake Natron.
Photographer Nick Brandt's eerie black and white photos allow both interpretations.
"I unexpectedly found the creatures — all manner of birds and bats — washed up along the shoreline of Lake Natron in Northern Tanzania. No one knows for certain exactly how they die, but it appears that the extreme reflective nature of the lake’s surface confuses them, and like birds crashing into plate glass windows, they crash into the lake.
"The water has an extremely high soda and salt content, so high that it would strip the ink off my Kodak film boxes within a few seconds. The soda and salt causes the creatures to calcify, perfectly preserved, as they dry," Brandt writes in his new photo/essay book, Across The Ravaged Land.
To give these obviously lifeless creatures an air of reanimation, Brandt picked them up off the shoreline and perched them in pre-death poses.
The lake's waters can reach temperatures up to 120 degrees Fahrenheit. During dry spells the pH can rise to 10.5, just shy of the alkalinity of ammonia. Sometimes the mineral to water ratio is so high that the water becomes almost thick to the touch.
Few living things can survive the super salty waters, with the exception of certain red-colored cyanobacteria (a type of blue-green algae) which give the lake a rust-colored appearance from space.
A single species of endemic fish can thrive in the corrosive environment: alkaline tilapia (Alcolapia latilabris).
Lesser flamingos take advantage of the inhospitable environment as a breeding ground. They feed off the blue-green algae in the lake and nest on islands of evaporated salt, or even along the dry, salty shorelines. It's such a good spot for nesting, in fact, that this lake is the only area where these 2.5 million birds will breed.
There's no need to fear predators because there are none. But the saline waters themselves can prove deadly if the birds aren't careful.
The lesser flamingo is now categorized as "near threatened" by the International Union for Conservation of Nature.
The Gelai Volcano sits on the southeastern shore of the 35-mile lake, towering 9,652 feet above the caustic waters.
Due to its unique ecosystem, the Lake Natron basin is on the Ramsar List of Wetlands of International Importance. Along with the region's significance to birdlife and other species come threats from nearby development. These threats include a proposed hydropower plant on the Ewaso Ngiro River, just over the border into Kenya, and a factory to process the soda ash from the lake itself.
Today nomadic peoples sometimes herd cattle through the region, but people do not live in the Lake Natron basin. The existing lake is a poisonously concentrated remnant of what used to be a huge, freshwater lake 5,000 to 6,000 years ago.
Even further back in the past, people did occupy this area. Just west of the lake is the resting place of Australopithecus boisei — the early East African hominin whose 1.75-million-year-old jaw and full set of teeth were found here in 1959. His dried bones are not unlike the calcified remains of Brandt's birds.
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