Marmots Are the Largest Members of the Squirrel Family

The Olympic marmot (Marmota olympus) is endemic to the Olympic Peninsula in Washington State, USA — it exists nowhere else on Earth. Found only above 1,500 meters in the subalpine meadows of Olympic National Park, this species has one of the most restricted ranges of any North American mammal. Climate change is shrinking its alpine habitat, and the species is considered vulnerable by conservation scientists.

While some marmot species are solitary, others like the yellow-bellied marmot and Olympic marmot are highly social. They live in colonies of up to 20 individuals structured around a dominant male, several females, and their offspring. Social bonds are reinforced through greeting behavior — marmots famously touch noses and nuzzle each other upon meeting, strengthening group cohesion vital for surviving long winters together.

In Central Asia, marmots — particularly the Tarbagan marmot (Marmota sibirica) — are a natural reservoir for Yersinia pestis, the bacterium that causes bubonic plague. In Mongolia, China, and Russia, eating or hunting sick marmots has caused sporadic plague outbreaks in humans. The 1911 Manchurian plague pandemic, which killed over 60,000 people, was traced to marmot hunting. Today, Central Asian countries maintain monitoring programs and ban the hunting of sick marmots.

Marmots are key ecosystem engineers in mountain environments. Their extensive burrowing aerates and turns over soil, improving drainage and plant growth. They are important prey for golden eagles, wolves, foxes, and bears. Their droppings fertilize the soil. By grazing selectively on alpine plants, marmots also help maintain plant diversity on high-altitude meadows across Europe, Asia, and North America.