An official website of the United States government
Here's how you know
Official websites use .gov A
.gov website belongs to an official government
organization in the United States.
Secure .gov websites use HTTPS A
lock (
) or https:// means you've safely connected to
the .gov website. Share sensitive information only on official,
secure websites.
After hiberating for up to eight months, yellow-bellied marmots emerge between February and May.
NPS/Neal Herbert
Yellow-bellied marmot track
Scientific Name
Marmota flaviventris
Identification
20–28 inches long; 3.5–11 pounds.
One of the largest rodents in Yellowstone.
Reddish-brown upper body; yellowish belly; small ears; prominent active tail.
Habitat
Found from lowest valleys to alpine tundra, usually in open grassy communities and almost always near rocks.
Feed on grasses and forbs in early summer; switch to seeds in late summer, occasionally will eat insects.
Prey for coyotes, grizzlies, and golden eagles.
Behavior
Hibernate up to 8 months, emerging from February to May depending on elevation; may estivate in June in response to dry conditions and lack of green vegetation and reappear in late summer.
Breed within two weeks of emerging from hibernation; average five young per year.
Active in morning, late afternoon, and evening.
Colonies consist of one male, several females, plus young of the year.
Vocalizations include a loud whistle (early settlers called them “whistle pigs”), a “scream” used for fear and excitement; a quiet tooth chatter that may be a threat.
Males are territorial; dominance and aggressiveness demonstrated by waving tail slowly back and forth.
