Wisconsin mammals

Muskrat in Wisconsin

Ondatra zibethicus

Native to Wisconsin S5 Secure in Wisconsin

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

IUCN Red List status

LC – Least Concern

Widespread and abundant; not at risk.

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

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 Wisconsin, by the numbers

Common in Wisconsin 10th most recorded of 75 mammals logged in Wisconsin

1,729 occurrence records

1,663 with iNaturalist photos

Jul 10, 2026 Last seen in Wisconsin

Records from 2000–2026.

1,729 total records count every Wisconsin occurrence from GBIF and iNaturalist; the map plots a georeferenced sample of 300; the monthly chart covers the 1,719 records with a full observation date.

When to look for the Muskrat in Wisconsin

Most sightings fall in March to May.

1,719 Wisconsin occurrence records (iNaturalist and GBIF) by month of year, 2000–2026. Shows when the species is recorded, not a guarantee of presence.

Monthly Wisconsin records (table)

Month	Records
January	64
February	63
March	256
April	328
May	286
June	174
July	156
August	90
September	62
October	49
November	106
December	85

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

Seasonality

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

Occurrence map

Where Muskrat has been recorded in Wisconsin

300 records mapped · zoom and drag to explore

300 Wisconsin records mapped

Notable places to look

Park, forest, or monument	iNaturalist records
Horicon Wildlife Area	24
Mead Wildlife Area	16
Richard Bong Recreation Area	10
Door County	7
Crex Meadows Wildlife Area	7
Green Bay West Shores Wildlife Area	7
Vernon Wildlife Area	6
Lake Mills Wildlife Area	5

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 Wisconsin

County	Records
Dane County	558
Waukesha County	108
Milwaukee County	100
Dodge County	99
La Crosse County	87
Portage County	63
Marathon County	57
Juneau County	54
Outagamie County	46
Winnebago County	39
Brown County	36
Kenosha County	36
51 other counties	446

The complete county distribution, spread across 63 Wisconsin counties. Every occurrence record falls in one county, so these sum to the total. Counties from GBIF and US Census boundaries.

Wisconsin records emphasize Horicon National Wildlife Refuge and the lakes, marshes, and slow-water edges around Kettle Moraine and nearby state parks. The March–May rise matches ice-out, fresh lodge visibility, and more open-water activity, making Muskrats easier to notice from boardwalks and shorelines.

The 1,663 iNaturalist records are observations, not an abundance estimate. Large public wetlands receive sustained visitation while small farm ponds and inaccessible marsh interiors receive little coverage, so record density mainly reveals where people looked.

Occurrence data from iNaturalist and GBIF.

Muskrat in other states

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 Wisconsin 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"