Lake Natron: Tanzania’s beautiful and deadly red lake

Apart from sometimes turning red, another reason that Lake Natron is so unusual is that it's incredibly caustic (alkaline) from the nearby volcano. This makes it poisonous to most animals. Animal and bird corpses can be found in and around the lake. This is why we refer to Lake Natron as Tanzania’s beautiful but deadly red lake.

Stick around so we can explain what turns the water red and makes it deadly, talk flamingoes, hikes and Maasai, and also introduce you to the active volcano on the lake's shore ...

Lake Natron as seen from space on 3 March 2017 | Image by NASA

Lake Natron is in northern Tanzania, just over a 100 km northwest of the city of Arusha. The elongated lake is 56 km long from north to south, and 24 km wide. A small portion of the lake – its northern tip – lies over the border in southern Kenya. 

As you can see in the map above, Lake Natron is perfectly positioned to be incorporated into a northern parks Tanzania safari.

We often take clients looking for a Big Five safari to Serengeti National Park and Ngorongoro Crater, but we now also offer a visit to Lake Natron as well.

One of the things we dig about Lake Natron is that it's so wildly different from its neighbouring attractions. It offers spectacular scenery that often seems implausible or unreal, as well as different wildlife, which even includes camels! And we also really appreciate how truly remote and sparsely populated it is.

Here are some facts you'll want to share with others for the wow factor!

Lake Natron receives only 400 mm of rain a year, and much of that is ‘phantom rain’ – rain that evaporates before hitting the surface. This is because the lake is in a desert.

The lake has no outlets, and receives most of its water from springs and episodic streams. Because the water coming into the lake leaches through the volcanic material of nearby Mt Ol Doinyo Lengai, the lake’s water is highly alkaline. 

Lake Natron contains large salt, soda and magnesite deposits. This is a good environment for the growth of a kind of bacteria that damages the innards of the organisms that drink it.

Flamingos aren't negatively affected by the bacteria in Lake Natron that harms most other birds. The lake is actually the largest breeding ground in the world for lesser flamingoes!

The water of Lake Natron sometimes turns red (or orange-red) because of the algae that thrives in its hypersaline environment. This red tinge to the water can even be seen from space!

The lake's temperature can rise to 60 °C (140 °F) in summer! There are also hot springs on its eastern shore.

Mt Ol Doinyo Lengai soars above Lake Natron and its countless water birds

The water of Lake Natron is very high in cyanobacteria. This is an algae that releases a chemical which in turn damages the cells, nervous system and livers of most of the organisms that have consumed it. Many of the birds and animals that drink from Lake Natron wind up dead as a result.

The animals, birds and bats that die in the water are calcified, and turn into mummified versions of themselves. The talented artist Nick Brandt has taken many of these petrified animals and placed them in lifelike poses, before snapping their photo. His series is titled Petrified.

View of the southern tip of Lake Natron, looking northwest | Image by Clem23

Parts of the lake often appear a deep red or orange. The cause of the colours is a type of algae.

A type of bacteria that flourishes in soda lakes often creates 'algae blooms', which in turn colour the water. The algae blooms of Lake Natron wax and wane, such that the lake's redness is not a fixed hue. The fringe of the lake also often looks more orange than red.

Only those who’ve never spent any real time in desert landscapes think of them as being simply dry, brown places. Because in reality, almost every desert is awash with many colours. Lake Natron and its surrounds are particularly hot on pinks and reds.

Consider that not only do you get the abundant red algae that is one of the claims to fame of the lake, but also: 

A desert rose (or impala lily) tree with Mt Ol Doinyo Lengai in the background

Mt Ol Doinyo Lengai (or Oldoinyo Lengai) is a perfectly conical, active volcano just to the south of Lake Natron. The highest point of Ol Doinyo Lengai is on its crater rim, and is 3,188 m (10,459 ft) above sea level. The crater itself is over 200 m deep and the lava inside it bubbles away at around 500ºC.

A cloud-shrouded Mt Ol Doinyo Lengai with Maasai huts in the foreground

An exciting challenge on offer to the ambitious hiker is summiting Mt Ol Doinyo Lengai.

As it’s so hot to climb during the day, many choose to hike it overnight. Starting at 10 pm, your Maasai guide leads you up the mountain.

The hike to the summit takes about six hours, and the descent takes about the same. You should be back at the base of the mountain mid morning. You’re then driven back to your camp for a hearty breakfast and well-earned splash in the pool! 

The lower portion of the trail mostly consists of loose soil. Higher up you're tackling some grass tufts, compressed ash, hardened lava and loose gravel. Note that the top half of the climb is very steep. Very steep. And you're climbing in the dark, guide by the light from your headlamp. So it's not at all a hike for the anxious! Trekking poles are useful for the descent.

Standing on the metre-wide crater rim and gazing into the fearsome, sulphur-emitting crater is both a heady and mesmerising experience. And the expansive views from Ol Doinyo Lengai of the Rift Valley as the rising sun illuminates the landscape are absolutely amazing.

If you'd like to read a personal account of the Mt Ol Doinyo Lengai summit hike, we can recommend Passport and Pixel's photo-rich blog post.

Crater rim of Mt Ol Doinyo Lengai – see the small person for scale!

Flamingoes are among the few birds that aren't harmed by the cyanobacteria of the lake. In fact, the one known side effect of their consumption of this particular bacteria is their pink hue! Certain other water birds, like storks, are also unaffected by the lake's cyanobacteria, and so can be found flourishing at Lake Natron.

Not only are flamingoes unharmed by the lake's cyanobacteria, they actually flourish because of the presence of a different bacteria, which is their food source. They thrive on the lake's algae-rich water so much, in fact, that at times there are over a million flamingoes at the lake! 

Flamingoes love to make a big racket when flying, emitting their hoarse calls

The flamingoes eat the lake's microscopic diatom algae. They eat upside down, in a sense, because they drop their heads down into the water and suck in the algae-rich water, which they filter for their food. The 'emptied' water is passed back out through their bills.

You can find both greater and lesser flamingos at the lake – in other words, the largest and smallest of flamingo species, and the only two species found in the Old World. The graphic below shows all of the different types of flamingoes.

Greater flamingoes can be found in many parts of the Old World, but lesser flamingoes live only in parts of sub-Saharan Africa and a small section of northwest India.

The greater and lesser flamingoes are the only Old World species of flamingoes – the rest live in the New World (i.e. the Americas)

The lake’s flamingoes mate between August and October. Their nests can be found in the soda flats on the lake’s southeastern shore. Made from mud, they look like miniature versions of the nearby volcano, Mt Ol Doinyo Lengai! Each flamingo lays one chalky white egg, which rests in its mud nest.

When the flaminglets are old enough to walk and swim, they form crèches, which are groups of young flamingoes. These crèches can reach 300,000 individuals. They're still only fed by their parents, but unrelated adult flamingoes help to look after them.

Flamingoes thrive on Lake Natron, even though the alkaline water is poisonous to most animals

Some of the other birds to look for while visiting Lake Natron are the:

A great white pelican on the shore of Lake Natron

The region surrounding Lake Natron isn’t somewhere you go specifically for game viewing. Nearby Serengeti and Ngorongoro are the spots for that. 

Rather, you go to Lake Natron to see the landscape: the desert lake, with its unusually coloured water, the flamingoes and other water birds, and the nearby volcano and escarpment.

But while there, do of course keep your eyes open for:

Camels drinking from Lake Natron | Image by R. Mortel

The Maasai are an ethnic group living in southern Kenya and northern Tanzania. They're a Nilotic people who migrated from south Sudan to their current territory around the 1700s.

The Maasai of the twenty-first century have resisted integration with modern society and pride themselves on retaining their cultural identity and traditional way of life, which includes herding and hunting. They're well recognised by their red and blue robes, and the women for their intricate and colourful beaded jewellery.

There are some remote Maasai communities living in the harsh and exacting environment around Lake Natron. Tourism-related jobs are a prominent source of income for many Maasai.

This Maasai gentleman is walking along an ash-covered escarpment in the Great Rift Valley

When you visit Lake Natron and Mt Ol Doinyo Lengai, you rent the services of local Maasai guides to show you around. These individuals can take you on a guided safari walk around the lake, a hike to Ngare Sero waterfall, or an overnight summit hike up Mt Ol Doinyo Lengai.

If you're travelling in the region with a tour operator like Follow Alice, our Tanzania safari tour guide, Kazi, drives you to the starting point of the chosen activity, where he hands you over into the care of the Maasai guide.

A Maasai man walks with his two dogs in the vicinity of Mt Ol Doinyo Lengai

A full-day and rewarding activity in the Lake Natron region is hiking to Ngare Sero Waterfall and back. This hike takes you up Ngare Sero Gorge, and at times requires you to scramble, climb, and walk through the water. But the water isn't ever very high – nothing above your hips.

The gorge grows increasingly steep and narrow the nearer you come to the waterfall, and early and late in the day you can experience some very welcome shade from its walls.

When you reach the waterfall, you can swim in its pool, a great treat after hiking in such a hot region! This is also the time to eat your picnic lunch and marvel at this oasis.

You can do a guided walk up the river to lovely Ngare Sero Waterfall

Those who are keen to do this hike must hire the services of a Maasai guide to lead them. You can't do this hike independently. The trailhead is a 30-minute drive from Lake Natron.

The trail itself is 5.5 km there and back, and you ascend a little over 300 m. Proper shoes are important, as the rocks are slippery. You'll want to wear water shoes, or be prepared to get your trainers wet.

You can learn more in Ngare Sero waterfall hike.

Lake Natron is in an arid, hot region. Temperatures can easily soar above 40 °C (104 °F).

July to early October is arguably the best time to visit the region for two reasons:

During the rainy season (late March to early May), certain roads to and from Lake Natron can become more difficult to navigate. That said, it's still totally possible to visit at that time – the drive just takes a little longer. The rainy season also brings some beautiful green softness to the region, so for some that's a drawcard.

If in doubt as to when to visit, we encourage you to chat with us. We can help advise you on the best time to travel to Lake Natron based on what you most want to do and see. We can also advise you as to when it's the best time to visit if you have other Tanzanian destinations in mind like Mt Kilimanjaro or Zanzibar.