The Olympic marmot lives only in Olympic Mountain meadows. It eats flowering plants, stores fat and hibernates for a long period.
Young animals are usually dark gray. Adult coat color changes with the seasons; it can look yellow or tan in spring, and some animals are nearly black in fall.
The Olympic marmot lives only on Washington State’s Olympic Peninsula. A 2025 study compared its genetic relationships with hoary and Vancouver Island marmots. The researchers analysed microsatellite data from five Olympic marmots and ultraconserved-element data from four individuals, using both sets alongside samples from related marmot populations in the Pacific Northwest.
The Olympic marmot formed a distinct genetic population in the analyses, and the study found no evidence of contemporary gene flow with the other included populations. Mitochondrial and nuclear data also gave different clues about the history of these related marmot lineages.
An extinction-risk assessment has not been added yet.
The Olympic marmot is restricted to Washington’s Olympic Peninsula. A 2025 study compared it with hoary and Vancouver Island marmots using microsatellite and ultraconserved-element data. Five Olympic marmots contributed microsatellite data and four contributed ultraconserved-element data; Vancouver Island marmots contributed five and two samples to those analyses. Olympic marmots formed a distinct population, with no contemporary gene flow detected between them and the other populations included in the study. Hoary marmots from Alaska, Canada and Montana were represented at ten sites; Washington hoary marmots were excluded.