Oregon mammals

Muskrat in Oregon

Ondatra zibethicus

Native to Oregon S5 Secure in Oregon

Not listed as nonindigenous in Oregon by USGS NAS; native to its Oregon range.

IUCN Red List status

  1. LC
  2. NT
  3. VU
  4. EN
  5. CR
  6. EW
  7. EX

LC – Least Concern

Widespread and abundant; not at risk.

Muskrats resting on a floating log in open waterMuskrat swimming head-on through calm waterLive muskrat sitting on a grassy bank at the water edgeTwo muskrats at a grassy water edgeMuskrat swimming with a long narrow tail trailing behind
Photo: Ken Clark · CC-BYMuskrats resting on a floating log in open waterPhoto: Svetlana Tsarakhova · CC0Muskrat swimming head-on through calm waterPhoto: Robert McLeod · CC0Live muskrat sitting on a grassy bank at the water edgePhoto: Dan Vickers · CC-BYTwo muskrats at a grassy water edgePhoto: Lukas Zangl · CC-BYMuskrat swimming with a long narrow tail trailing behind

Muskrat in Oregon, by the numbers

Common in Oregon 36th most recorded of 178 mammals logged in Oregon

846 occurrence records
593 with iNaturalist photos
Jul 4, 2026 Last seen in Oregon

Records from 2000–2026.

846 total records count every Oregon occurrence from GBIF and iNaturalist; the map plots a georeferenced sample of 300; the monthly chart covers the 768 records with a full observation date.

When to look for the Muskrat in Oregon

Most sightings fall in March to June.

768 Oregon occurrence records (iNaturalist and GBIF) by month of year, 2000–2026. Shows when the species is recorded, not a guarantee of presence.

Monthly Oregon records (table)
MonthRecords
January55
February49
March103
April109
May87
June69
July54
August48
September35
October21
November46
December92

Monthly muskrat occurrence records (iNaturalist and GBIF) in Oregon, 2000–2026.

Seasonality

Year-round in Oregon, with recorded sightings peaking in March–June, with a smaller rise in December.

Occurrence map

Where Muskrat has been recorded in Oregon

300 records mapped · zoom and drag to explore

300 Oregon records mapped

Notable places to look

Park, forest, or monumentiNaturalist records
Summer Lake Wildlife Area 17
Klamath Wildlife Area 8
E.E. Wilson Wildlife Area 4
Winema National Forest 3
Siuslaw National Forest 3
Sauvie Island Wildlife Area 2
Lewis and Clark National Historical Park 2
Gifford Pinchot National Forest 2

Protected places with the most muskrat sightings, from the USGS Protected Areas Database plus named mountain ranges, good spots to look, not a full breakdown, so they don't sum to the total.

Where it's recorded in Oregon

CountyRecords
Washington County 153
Multnomah County 106
Lane County 82
Klamath County 73
Lake County 60
Marion County 50
Clatsop County 38
Harney County 37
Deschutes County 27
Columbia County 17
Jackson County 17
Umatilla County 17
24 other counties 169

The complete county distribution, spread across 36 Oregon counties. Every occurrence record falls in one county, so these sum to the total. Counties from GBIF and US Census boundaries.

Oregon muskrat records follow water rather than a single broad region, linking Willamette Valley wetlands with Cascade lakes and marshes in the drier interior. Documentation is highest from March through May and drops markedly after midsummer, although some records occur in every month. These are records of visible animals and observer access to wetlands, not an abundance estimate.

Occurrence data from iNaturalist and GBIF.

Muskrat in other states

Muskrats resting on a floating log in open water
Full species profile Muskrat Ondatra zibethicus Size 25–36 cm9.8–14.2 in Weight 0.6–2 kg1.3–4.4 lb Lifespan 3 yr View the full profile

More mammals in Oregon in the atlas

Data & sources

The data and visualizations on this page draw on these open sources:

  • GBIFCC-BY 4.0occurrence records behind the range map, elevation, and record counts
  • iNaturalistCC0 / CC-BY / CC-BY-SAobservations, photos, and audio recordings
  • NatureServe ExplorerCC-BYthe state conservation rank
  • IUCN Red Listattributed factthe global conservation status
  • USGS NASpublic domainnative / introduced status
  • Natural Earthpublic domainthe relief basemap
  • USFSpublic domainnational-forest boundaries
  • USGS Protected Areas Databasepublic domainthe named parks, forests, and refuges behind "notable places to look"