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It is one of the aquatic marvels of the world, a virtual inland sea so vast that it has been called the Australia of fresh waters. But scientists and environmentalists say that Lake Baikal—the world’s oldest and largest lake in terms of volume—is sliding toward an ecological catastrophe due to continuing industrial contamination that has its roots in the Cold-War era.

Eye in the Sky

Two unexplained die-offs of nerpa seals—the only freshwater seals in the world—during the past three years has heightened concerns.

“Baikal has become a symbol of environmental dangers,” according to Amy Van Allen, author of a recent American University study of the lake—which has been celebrated by poets and scientists alike for its size, age, and the startling clarity of its frigid waters. “The similarities of Lake Baikal to other bodies of water indicate these dangers and the urgency of conservation.”

Allen compared Baikal to the U.S.-Canadian Great Lakes, now believed on the rebound after years of abuse. As a worst-case outcome, she cited Lake Tanganyika—which, unlike teeming Baikal, is all but lifeless.


Located in southern Siberia, Baikal’s watershed extends over the Mongolian border. An old Siberian song refers to it as “Ye glorious sea, ye sacred Baikal.” Russians call it “The Pearl of the East.”

Officials of the old Soviet Union once believed the lake’s very size would protect it and its 1,500 unique species of plants and animals from an onslaught of industrial pollutants. The environmental assault began in the 1950s as part of Soviet efforts to keep up with the West militarily.

Soviet citizens first heard in 1957 about plans for a huge plant on the lakeshore at Baykalsk to produce cellulose to toughen the tires on military jets. Their protests sparked an environmental movement that served as a model for the country’s subsequent grass-roots activism.

The Baykalsk Paper and Pulp Mill was built nonetheless, and the pollution has continued long after it was converted to a more peaceful purpose: producing bleached cellulose used to manufacture clothing. The mill’s output is now the second highest in Russia.

The latest evidence that something is wrong with the water was found in June 1999, when the bodies of 78 nerpa seals washed up on shores near the villages of Utulik and Baykalsk.

Nerpas have suffered mysterious mass die-offs before: in the 1930s, in 1988, and again in 1997. An infectious disease was suspected in the first two. But scientists and environmental activists are pointing to the two most recent incidents, occurring within a year of each other, as evidence that the seals’ natural immune systems are being compromised by pollution. A report by Russian and other scientists pinpointed dioxins from the mill as a possible culprit.

The water isn’t the only thing that’s being dirtied. The American University study called the rate of air pollution surrounding Baykalsk among the worst in Russia.


Even before the 1991 demise of the old Soviet Union, the government had begun responding to pressure from the country’s burgeoning environmental movement. In 1987, authorities issued a decree ending shore logging. The mill was to undergo renovations that would reduce pollution, and the area around Baikal was designated for reserves and parkland. An international ecological center was created in 1990.

However, then and now, the government proved unable to provide funding for all the remedies that had been recommended. Simply closing the mill is not an attractive option, since it provides important economic benefits to the region, including 3,500 jobs.

Among the most recent initiatives by park officials to raise funds for wildlife protection programs has been encouragement of ecotourism. Earth Island Institute, a San Francisco-based environmental group, operates Baikal Watch, which supports the protected areas and organizes ecotours.

For now, most scientists agree that the nerpa seals and other species found nowhere else in the world—including the omul salmon—are not in danger of extinction due to the huge size of the lake and its ability to regenerate its waters. But they warn that if the pollution of Baikal’s waters and surrounding air is not reduced, other animals will suffer—including the human residents.

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•  Clay samples show that Lake Baikal is at least 30 million years old, making it the world’s oldest known lake.
•  At more than one mile (1,637 meters) deep, Lake Baikal is the world’s deepest lake.
•  The lake lies on one of the two deepest land depressions on Earth, the other being the Mariana Trench in the Pacific Ocean.
•  Lying at the juncture of three tectonic plates, the region around Lake Baikal experiences minor earthquakes every few hours.

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Because of its relative isolation from other bodies of water, Lake Baikal has been called the aquatic equivalent of the Galápagos Islands. Over millions of years of interbreeding, some 1,500 species found nowhere else on Earth have evolved in the lake’s crystal clear waters.

These include the omul, a salmon considered a delicacy in the region. But perhaps the most remarkable animal is the Baikal seal—also called the nerpa—the world’s only freshwater seal, and one of its smallest.

Nerpas are believed to be relatives of the Arctic ringed seal, found 2,000 miles (3,220 kilometers) away. Although no one knows for certain, scientists estimate their total population at about 68,000.

Scientists suspect that industrial pollution is responsible for two recent mass die-offs of nerpas. They have found residues of dioxins, PCBs and DDT in dead seals. Other threats include toxic chlorinated pesticides that have appeared at elevated levels around industrial discharges.

Conservationists believe the nerpa is also endangered by over-hunting. They estimate that more than 5,000 seals are taken annually by local hunting collectives located around the lake—a rate that they say is unsustainable.