Over 100 Dead Seals Wash Ashore At The World’s Deepest Lake

In the depths of Siberia, the world’s deepest lake is under threat. Holding one-fifth of all unfrozen freshwater, Lake Baikal is an internationally significant site, but in recent times there have been indications that something's not quite right. Now, over 100 dead Baikal seals have been found washed up on the lake's shore.

“There were about 130 animals found dead,” environmental ministry spokesman, Nikolai Gudkov, told AFP. “We took water samples to understand whether we can talk of water pollution as the reason.”

This latest news feeds into wider concerns about the lake's ecological state, which some worry is on the brink of collapse. Fish stocks have plummeted, prompting the government to ban the catching of certain species of high importance, as vast stretches of endemic species of freshwater sponges have been decimated and huge growths of putrid algae have bloomed. There are suggestions that the death of the seals is linked to the crash in fish numbers.  

The lake is capped with solid ice for nearly half the year. Katvic/Shutterstock

The Lake Baikal seals are unique among pinnipeds, being not only the smallest species but also the only exclusively freshwater seal known to science. One of the biggest mysteries surrounding the creatures is how they ended up in the lake in the first place, which lies hundreds of kilometers from the coast. It is assumed that around 2 million years ago some of the marine mammals must have swum up rivers before becoming trapped, or that perhaps the lake was once connected to the sea.

The lake is of massive significance as it holds so much of the planet’s liquid fresh water and is the oldest lake in the world. As such, despite being covered by a thick layer of ice for five months each year, the ecosystem that has developed in the lake is astonishing and like few others. It is estimated that 80 percent of plants and animals that live in it are found nowhere else on the planet, and yet many of these creatures are now facing a threat to their survival.

Algae blooms are becoming more common and destroying large fields of endemic sponges. Elena Kitch/Shutterstock

One of the main concerns for those studying the lake is the huge amount of pollution pouring into the water from surrounding developments. This wastewater run, one Russian scientist said, is contributing to the blooms of algae that are smothering the sponge forests on the seabed. It is also thought that the impacts of climate change in the region are playing their part as well.

The Russian government, for its part, is trying to help with the pollution, putting $452 million into a fund to help the clean-up efforts.

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