Maryland mammals

Muskrat in Maryland

Ondatra zibethicus

Native to Maryland S5 Secure in Maryland

Not listed as nonindigenous in Maryland by USGS NAS; native to its Maryland 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 Maryland, by the numbers

Common in Maryland 12th most recorded of 100 mammals logged in Maryland

751 occurrence records

Records from 2000–2026.

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

When to look for the Muskrat in Maryland

Most sightings fall in April to May.

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

Monthly Maryland records (table)
MonthRecords
January46
February51
March90
April175
May148
June71
July40
August38
September16
October11
November13
December30

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

Seasonality

Year-round in Maryland, with recorded sightings peaking in April–May.

Occurrence map

Where Muskrat has been recorded in Maryland

300 records mapped · zoom and drag to explore

300 Maryland records mapped

Notable places to look

Park, forest, or monumentiNaturalist records
Harriet Tubman Underground Railroad National Historical Park 77
Chesapeake and Ohio Canal National Historical Park 48
Patuxent Oxbow Heritage Conservation 14
George Washington Memorial Parkway 11
Deep Creek Lake Natural Resource Management Area 6
Assateague Island National Seashore 6
Mckee Beshers Wildlife Management Area 5
Calvert Cliffs State Park 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 Maryland

CountyRecords
Montgomery County 126
Dorchester County 120
Prince George's County 97
Baltimore County 74
Anne Arundel County 57
Calvert County 26
Garrett County 26
Frederick County 23
Howard County 23
Queen Anne's County 20
Carroll County 16
Caroline County 16
11 other counties 127

The complete county distribution, spread across 23 Maryland counties. Every occurrence record falls in one county, so these sum to the total. Counties from GBIF and US Census boundaries.

Muskrats inhabit Maryland’s freshwater and brackish marshes, ponds, and slow waterways. Blackwater and Eastern Neck are strong places to scan channel edges for low swimming profiles, feeding platforms, bank burrows, or compact vegetation houses, especially early or late in the day.

Records extend through the year and are strongest from March through May. Marsh vegetation can conceal animals later in the season, so visible signs and open-water routes may be more informative than raw sighting totals.

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 Maryland 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"