Michigan mammals

Masked Shrew in Michigan

Sorex cinereus

Native to Michigan S5 Secure in Michigan

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

Sorex cinereus, Harwich, Chatham, Ontario, Canada 1Sorex cinereus, Harwich, Chatham, Ontario, Canada 2Sorex cinereus, Harwich, Chatham, Ontario, Canada 3Sorex cinereus, Harwich, Chatham, Ontario, Canada 4Sorex cinereus, Billings National Historical Park, Woodstock, Vermont, USA 1Masked Shrew (Sorex cinereus)
Photo: rpoort · CC BY 4.0Sorex cinereus, Harwich, Chatham, Ontario, Canada 1Photo: rpoort · CC BY 4.0Sorex cinereus, Harwich, Chatham, Ontario, Canada 2Photo: rpoort · CC BY 4.0Sorex cinereus, Harwich, Chatham, Ontario, Canada 3Photo: rpoort · CC BY 4.0Sorex cinereus, Harwich, Chatham, Ontario, Canada 4Photo: er-birds · CC BY 4.0Sorex cinereus, Billings National Historical Park, Woodstock, Vermont, USA 1Photo: Sean Frey · CC BY 4.0Masked Shrew (Sorex cinereus)

Masked Shrew in Michigan, by the numbers

Common in Michigan 25th most recorded of 75 mammals logged in Michigan

410 occurrence records
46 with iNaturalist photos
Apr 20, 2026 Last seen in Michigan

Records from 2000–2026.

410 total records count every Michigan occurrence from GBIF and iNaturalist; the map plots a georeferenced sample of 300; the monthly chart covers the 409 records with a full observation date.

When to look for the Masked Shrew in Michigan

Most sightings fall in August to October.

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

Monthly Michigan records (table)
MonthRecords
January3
February3
March1
April6
May7
June40
July46
August111
September98
October88
November2
December4

Monthly masked shrew occurrence records (iNaturalist and GBIF) in Michigan, 2000–2026.

Seasonality

Year-round in Michigan, with recorded sightings peaking in August–October.

Occurrence map

Where Masked Shrew has been recorded in Michigan

300 records mapped · zoom and drag to explore

300 Michigan records mapped

Notable places to look

Park, forest, or monumentiNaturalist records
Ottawa National Forest 159
Gaylord State Forest Area 6
University of Michigan Biological Station 2
Pigeon River Country State Forest Area 2
Pinckney Recreation Area 1
Porcupine Mountains Wilderness State Park 1
Gwinn State Forest Area 1
Port Crescent State Park 1

Protected places with the most masked shrew 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 Michigan

CountyRecords
Gogebic County 159
Schoolcraft County 54
Kalkaska County 47
Cheboygan County 40
Mackinac County 17
Chippewa County 15
Otsego County 14
Washtenaw County 6
Ontonagon County 5
Menominee County 5
Marquette County 4
Muskegon County 4
23 other counties 40

The complete county distribution, spread across 35 Michigan counties. Every occurrence record falls in one county, so these sum to the total. Counties from GBIF and US Census boundaries.

Cinereus shrew records connect several of Michigan’s major northern landscapes: Ottawa National Forest and the Keweenaw in the western Upper Peninsula, Seney’s wetland-forest mosaic in the east, and the Huron-Manistee forests below the Straits. The spread suggests records from moist forest floor, wet meadow edge, and woody debris across both peninsulas.

Michigan submissions rise in June and again from August through October. Small shrews are seldom noticed casually, so these records reflect trapping, close observation, and identification effort rather than abundance or a complete distribution map.

Occurrence data from iNaturalist and GBIF.

Sorex cinereus, Harwich, Chatham, Ontario, Canada 1
Full species profile Masked Shrew Sorex cinereus Size 6.9 cm2.7 in Weight 5 g0.2 oz Lifespan Up to 2.5 yr View the full profile

More mammals in Michigan 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"