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 57 mammals logged in Maryland

984 occurrence records
984 with iNaturalist photos

Records from 2000–2026.

984 total records count every Maryland occurrence from GBIF and iNaturalist; the map plots a georeferenced sample of 300; the monthly chart covers the 946 records with a full observation date.

When to look for the Muskrat in Maryland

Most sightings fall in April to May.

946 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
January35
February47
March116
April236
May209
June96
July64
August47
September26
October12
November19
December39

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 91
Chesapeake and Ohio Canal National Historical Park 60
George Washington Memorial Parkway 19
Patuxent Oxbow Heritage Conservation 13
Mckee Beshers Wildlife Management Area 10
Assateague Island National Seashore 8
Deep Creek Lake Natural Resource Management Area 8
Calvert Cliffs State Park 4

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 167
Dorchester County 129
Prince George's County 122
Baltimore County 90
Anne Arundel County 73
Calvert County 53
Frederick County 31
Queen Anne's County 31
Garrett County 29
Howard County 26
Allegany County 23
Carroll County 21
11 other counties 189

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

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 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"