50 Fun Facts About Lake Baikal

Lake Baikal is on which continent?

Asia. The lake lies deep in Siberia, far from any ocean, yet it has its own species of seal, the only one in the world that lives solely in fresh water.

Lake Baikal, the oldest and most voluminous freshwater lake, is also the world's what?

Deepest. Its floor lies more than a kilometre below sea level, even though the lake's surface sits about 455 metres above it.

Lake Baikal holds roughly what share of all the fresh water on Earth's surface?

About 20%. That is roughly as much as all five of North America's Great Lakes combined, though Lake Superior alone spreads over more than twice Baikal's area.

Roughly how old is Lake Baikal?

About 25 million years. So much time in isolation let evolution run its own course: most of the animal species in the lake live nowhere else on Earth.

Lake Baikal's surface area is slightly larger than which European country?

Belgium. Baikal covers more than 31,000 square kilometres, yet it is a long, narrow lake: about 636 km from end to end but less than 80 km across at its widest.

Lake Baikal sits in what kind of geological feature?

A rift valley. The Earth's crust is slowly pulling apart there, and as the gap widens the valley floor keeps sinking.

Which African lake is second only to Baikal in the volume of fresh water it holds?

Lake Tanganyika. Like Baikal it is long and narrow, but it lies in the tropics, with crocodiles and hippos along its shores instead of seals.

Seismic surveys show that Lake Baikal's water rests on a layer, several kilometres thick, of what?

Sediment. Ice sheets never scraped it away, so cores drilled from it hold a record of the region's climate going back millions of years.

Which Siberian city stands on Lake Baikal's only outflowing river, about 70 km from the lake?

Irkutsk. It began in the 1650s as a winter camp for collecting fur tribute and grew into the hub of Russia's overland trade with China and Mongolia.

Which river is the only one that flows out of Lake Baikal?

The Angara. It is the lake's only exit, and a hydroelectric dam built across it in the 1950s raised the level of the entire lake.

Roughly how many rivers and streams flow into Lake Baikal?

About 330. Yet only a single river carries all of that water out again.

Which river, rising in Mongolia, provides almost half of Lake Baikal's inflow?

The Selenga. It is Mongolia's principal river, so close to half of the water flowing into Baikal begins its journey in another country.

How far down can you see through Lake Baikal's water at its clearest?

About 40 metres. Baikal's water holds very few dissolved minerals, which helps make it one of the clearest lakes in the world.

Lake Baikal's surface freezes over in January and usually stays frozen until which month?

May. The ice lingers longest in the north, and those frozen months are when the lake's seals give birth, raising their pups on the ice before it melts.

Which island is the largest in Lake Baikal?

Olkhon. Despite sitting in the middle of a vast lake it is a dry island: forest covers its north, but the south is open steppe grassland.

Which animal is the only known natural predator of adult Baikal seals?

The brown bear. Even bears catch them only occasionally, so apart from human hunters the seals have no other significant enemy.

The strait between Lake Baikal's largest island and its western shore is called Maloye More, meaning what?

The Little Sea. Russians long spoke of Baikal itself as a sea, and the 19th-century folk song 'Glorious Sea, Sacred Baikal' still does.

Which Russian leader rode a mini-submarine to the bottom of Lake Baikal in 2009?

Vladimir Putin. Then prime minister, he surfaced saying he had seen practically no pollution, and soon afterwards ordered a shuttered lakeside mill to reopen.

What is the local name for the Baikal seal?

Nerpa. It is among the smallest of all seals, about 1.3 metres long, yet it can dive as deep as 400 metres to hunt.

The Baikal seal is most closely related to which Arctic species?

The ringed seal. The two share the genus Pusa, which suggests the Baikal seal's ancestors came from Arctic waters, though how they reached a lake so far inland is still debated.

How do Baikal seals breathe when the lake freezes over?

Through holes clawed in the ice. Each seal keeps its holes open all winter by scraping them with its strong claws, and it stays close to them until the thaw.

What colour is a Baikal seal pup's natal coat?

White. Pups are born on the lake ice in late winter and keep the woolly white coat for about six weeks before moulting into adult grey.

Which translucent, scaleless fish is the main food of the Baikal seal?

The golomyanka. Also called the Baikal oilfish, it is the most abundant fish in the lake, yet it is not fished commercially because it never gathers in large shoals.

How do female Baikal oilfish reproduce?

They give birth to live larvae. The young develop inside the mother for about three months and emerge as a swarm of thousands instead of hatching from eggs.

Which whitefish found only in Lake Baikal is traditionally smoked and sold in lakeside markets?

The omul. Its stocks fell so far that in October 2017 Russia banned all commercial fishing for it, fearing irreversible harm to the population.

Scientists link the 'giant' size of some Lake Baikal crustaceans to the water's high level of what?

Oxygen. A 1999 study of 1,853 amphipod species worldwide found that the more of it the water holds, the larger they can grow, and Baikal's cold water is rich in it.

Which animals form branching green 'forests' on the bed of Lake Baikal?

Sponges. Some stand a metre tall, unusually big for fresh water, and scientists reported in 2017 that many of these underwater forests had died.

The Barguzin reserve, founded on Lake Baikal's shore in 1916, was created to protect which prized fur animal?

The sable. Barguzin's sables were famed for near-black fur that fetched very high prices, so the reserve was set up to rebuild their numbers.

Which Russian writer crossed Lake Baikal by steamer in 1890 on his way to Sakhalin?

Anton Chekhov. In a letter home he called the water turquoise and so clear that seeing rocks far below 'sent a shiver all over' him.

Which indigenous people raise goats, camels and horses on Lake Baikal's eastern shore?

The Buryats. They are the northernmost of the main Mongol peoples and traditionally nomadic herders, which is why camels can be found grazing beside a Siberian lake.

The icebreaking ferry that carried trains across Lake Baikal from 1900 was built in which country?

England. Shipbuilders on the Tyne assembled it, took it apart again and sent it to Siberia in about 7,000 pieces to be rebuilt on the lakeshore.

The line built around Lake Baikal's southern tip by 1905 closed the gap in which railway?

Trans-Siberian. The lakeside stretch had to be cut through cliffs with dozens of tunnels, and it became known as the 'golden buckle on the steel belt of Russia'.

In the Great Siberian Ice March of 1920, which retreating army crossed the frozen surface of Lake Baikal?

The White Army. Admiral Kolchak's beaten forces had already retreated some 2,000 km across Siberia in winter, and many froze to death on the windswept ice.

Which foreign military force fought a minor engagement with the Red Army at Lake Baikal in 1918?

The Czechoslovak Legion. Its soldiers armed two captured steamers with howitzers and set the Reds' armed icebreaker ablaze: a naval victory for men from a landlocked homeland.

Decades of protest failed to shut the Baykalsk mill beside Lake Baikal; what finally closed it in 2013?

Bankruptcy. The reason was financial, not ecological: its creditors stopped production, although scientists had protested against the mill ever since the 1960s.

The Baykalsk mill, long accused of pouring chlorine-bleaching waste into Lake Baikal, made which product?

Paper pulp. Soviet planners put the mill there because Baikal's water was pure enough to make high-grade pulp for the aerospace industry with almost no treatment.

Which two submersibles took Russian scientists to the bottom of Lake Baikal in July 2008?

Mir-1 and Mir-2. A year earlier the same two submersibles had dived beneath the North Pole, where their crews planted a Russian flag on the seabed.

What kind of scientific instrument has operated beneath Lake Baikal since the 1990s?

A neutrino telescope. Its strings of light sensors hang about a kilometre down, and an enlarged array commissioned in 2021 was then the largest neutrino telescope in the Northern Hemisphere.

What does Epischura, a tiny crustacean found only in Lake Baikal, do for the lake?

Filters the water clean. It makes up most of the lake's animal plankton and grazes on the microscopic plants drifting there, straining so much water each year that it helps keep Baikal clear.

Because of its many unique species, UNESCO calls Lake Baikal the 'what' of Russia?

Galápagos. Like those islands, the lake was cut off for so long that evolution produced animals found nowhere else, among them a freshwater seal.

Fed by untreated sewage, thick rotting mats of what have blanketed some of Lake Baikal's beaches since the 2010s?

Algae. Scientists blame phosphate-rich wastewater from lakeside towns, a sign that even this vast lake can no longer absorb pollution without consequence.

In 2006, protests over earthquake risk led Russia's president to order what moved 40 km away from Lake Baikal?

An oil pipeline. Campaigners feared a quake could rupture it and spill crude into the lake, and the order overruled the state's own environment watchdog, which had backed the lakeside route.

DNA from the 24,000-year-old 'Mal'ta boy', buried near Lake Baikal, revealed a surprising link to which people?

Native Americans. His genome showed that part of their ancestry came from his people, who were closer to western Eurasians than to East Asians.

Which feature, better known from the deep ocean floor, have scientists found on the bed of Lake Baikal?

Hydrothermal vents. Hot water rises through breaks in the Earth's crust beneath the lake, and breaks like them feed hot mineral springs around its shores.

Which is the only lake in Eurasia larger than Baikal by surface area?

The Caspian Sea. The Aral Sea was once more than twice Baikal's size as well, but it has shrunk to a fraction of that since its rivers were diverted for irrigation.

What name is given to the region lying east of Lake Baikal?

Transbaikalia. The name means 'beyond Baikal', the viewpoint of Russians arriving from the west, for whom this land lay on the far side of the lake.

Lake Baikal's only outflowing river is a tributary of which great Siberian river?

The Yenisey. Rain that falls in Mongolia can therefore flow through Baikal and on for thousands of kilometres to the Kara Sea, on Siberia's Arctic coast.

Compared with the surrounding region, what effect does Lake Baikal's huge mass of water have on winters along its shores?

It makes them milder. The lake is so slow to cool that it does not freeze over until January, about two months after the rivers that feed it.

A Chinese-backed plant on Lake Baikal sparked protests over plans to export what?

Bottled water. In 2019 nearly a million people signed a petition against the plant, fearing it would harm the lake, and a court ordered construction to stop.

Lake Baikal is the only freshwater lake known to hold 'burning ice', a frozen solid that locks up what?

Natural gas. The solid, called a gas hydrate, forms only under cold and great pressure, conditions otherwise found beneath the ocean floor.