Maryland mammals

House Mouse in Maryland

Mus musculus

Introduced to Maryland

Maryland's Mus musculus records are of an introduced species; it does not occur here as a wild native population.

IUCN Red List status

LC – Least Concern

Widespread and abundant; not at risk.

Photo: hatwise · CC BY 4.0House mouse in dry plant litterPhoto: dandri · CC0House mouse on concrete near green plantsPhoto: trisairatops · CC BY 4.0House mouse beside a curbPhoto: hatwise · CC BY 4.0House mouse moving through dry stemsPhoto: hatwise · CC BY 4.0House mouse partly hidden in leaf litter

Photo: hatwise · CC BY 4.0House mouse in dry plant litterPhoto: dandri · CC0House mouse on concrete near green plantsPhoto: trisairatops · CC BY 4.0House mouse beside a curbPhoto: hatwise · CC BY 4.0House mouse moving through dry stemsPhoto: hatwise · CC BY 4.0House mouse partly hidden in leaf litter

House Mouse in Maryland, by the numbers

Common in Maryland 17th most recorded of 100 mammals logged in Maryland

229 occurrence records

Records from 2000–2026.

229 total records count every Maryland occurrence from GBIF and iNaturalist; the monthly chart covers the 228 records with a full observation date.

When to look for the House Mouse in Maryland

Most sightings fall in August to September.

228 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)

Month	Records
January	11
February	13
March	12
April	10
May	14
June	15
July	20
August	52
September	37
October	22
November	3
December	19

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

Seasonality

Year-round in Maryland, with recorded sightings peaking in August–September.

Occurrence map

Where House Mouse has been recorded in Maryland

229 records mapped · zoom and drag to explore

229 Maryland records mapped

Where it's recorded in Maryland

County	Records
Anne Arundel County	96
Baltimore County	37
Montgomery County	24
Dorchester County	21
Frederick County	14
Prince George's County	8
Worcester County	7
Harford County	5
Howard County	4
St. Mary's County	4
Cecil County	1
Queen Anne's County	1
2 other counties	7

The complete county distribution, spread across 14 Maryland counties. Every occurrence record falls in one county, so these sum to the total. Counties from GBIF and US Census boundaries.

House Mice in Maryland are introduced commensals found mainly in buildings, barns, warehouses, and other human-altered settings. Their appearance in biodiversity records reflects incidental encounters and trapping more than wildlife watching, and refuge labels should not be treated as recommended viewing destinations for this species.

Records occur in every season and peak in August and September. Reporting effort and access to structures strongly shape that pattern, so it is not a direct index of outdoor abundance.

House Mouse in other states

Louisiana

Full species profile House Mouse Mus musculus Size 5–10 cm2–3.9 in Weight 12–30 g0.4–1.1 oz Lifespan Up to 4 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