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 33rd most recorded of 178 mammals logged in Oregon

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

Records from 2000–2026.

617 total records count every Oregon occurrence from GBIF and iNaturalist; the map plots a georeferenced sample of 300; the monthly chart covers the 595 records with a full observation date.

When to look for the Muskrat in Oregon

Most sightings fall in March to May.

595 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
January27
February40
March80
April106
May84
June62
July58
August46
September29
October16
November18
December29

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

Seasonality

Year-round in Oregon, with recorded sightings peaking in March–May.

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 14
Klamath Wildlife Area 8
E.E. Wilson Wildlife Area 4
Winema National Forest 3
Sauvie Island Wildlife Area 2
Whitman National Forest 1
Lewis and Clark National Historical Park 1
Ladd Marsh Wildlife Area 1

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 152
Multnomah County 85
Klamath County 52
Lane County 40
Deschutes County 26
Lake County 25
Harney County 23
Clatsop County 19
Jackson County 17
Columbia County 15
Umatilla County 12
Marion County 12
23 other counties 139

The complete county distribution, spread across 35 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

Muskrat range map (all 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"