Olympic marmots eat meadow flora such as avalanche and glacier lilies, heather blossoms, subalpine lupine, mountain buckwheat, harebells, sedges, and mosses.
They prefer green, tender, flowering plants over other sources of food, but roots are a large part of their diets in the early spring when other plants have not yet appeared.
During May and June, they may resort to gnawing on trees for food.
They also occasionally eat fruits and insects.
Their water requirements are met from the juice in the vegetation they eat and dew on the plants' surfaces.

When snowfall covers vegetation, marmots have a more carnivorous diet, consuming carrion encountered while digging for roots and possibly killing late hibernating chipmunks.
At this time, they also obtain water from melted snow.
Hibernating Olympic marmots do not keep food in their burrows; instead, they gain fat before hibernating and can double their body weight to survive eight months without eating.
Olympic marmots eat meadow flora such as avalanche and glacier lilies, heather blossoms, subalpine lupine, mountain buckwheat, harebells, sedges, and mosses. They prefer green, tender, flowering plants over other sources of food, but roots are a large part of their diets in the early spring when other plants have not yet appeared. During May and June, they may resort to gnawing on trees for food. They also occasionally eat fruits and insects. Their water requirements are met from the juice in the vegetation they eat and dew on the plants' surfaces.
When snowfall covers vegetation, marmots have a more carnivorous diet, consuming carrion encountered while digging for roots and possibly killing late hibernating chipmunks. At this time, they also obtain water from melted snow. Hibernating Olympic marmots do not keep food in their burrows; instead, they gain fat before hibernating and can double their body weight to survive eight months without eating.
Olympic marmot