This pristine lake has endured for 2m years. Why are its fish in crisis?

In one of the world's oldest lakes, Hovsgol grayling, a species found only in these azure waters in Mongolia, are struggling to survive

Words and photos by Anne Readel

Pine-studded mountains and snow-capped hills fringe Mongolia's ancient Lake Hovsgol. Wild flowers cascade down its steep banks, and its forests harbour wolves, moose and elk. Despite its remoteness, small towns, tourist lodges and pastoralists' gers - the traditional Mongolian circular felt tents - are sprinkled along the shore, along with herds of sheep, goats and yaks.

Located in north Mongolia, a few miles from Russia, Lake Hovsgol is the country's deepest and largest lake by volume. It is known locally as the Blue Pearl for its translucent azure water, and is considered one of the most pristine lakes in the world. It is also one of the oldest, formed more than 2m years ago.

Goats, horses, and yaks graze along the shore of Lake Hovsgol. Overgrazing and more frequent storms are degrading pastures used by herders, meaning many are turning to fishing to supplement their income