Connecticut mammals

Masked Shrew in Connecticut

Sorex cinereus

Native to Connecticut S5 Secure in Connecticut

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

IUCN Red List status

LC – Least Concern

Widespread and abundant; not at risk.

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)

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 Connecticut, by the numbers

Occasional in Connecticut 36th most recorded of 70 mammals logged in Connecticut

37 occurrence records

21 with iNaturalist photos

Jun 26, 2026 Last seen in Connecticut

Records from 2000–2026.

37 total records count every Connecticut occurrence from GBIF and iNaturalist; the map plots a georeferenced sample of 36; the monthly chart covers the 34 records with a full observation date.

When to look for the Masked Shrew in Connecticut

Most sightings fall in September.

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

Monthly Connecticut records (table)

Month	Records
January	1
February	1
March	1
April	1
May	7
June	7
July	1
August	1
September	8
October	2
November	2
December	2

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

Seasonality

Year-round in Connecticut, with recorded sightings peaking in September, with a smaller rise in May–June.

Occurrence map

Where Masked Shrew has been recorded in Connecticut

36 records mapped · zoom and drag to explore

36 Connecticut records mapped

Notable places to look

Park, forest, or monument	iNaturalist records
Talbot Wildlife Area	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 Connecticut

County	Records
Litchfield County	9
New Haven County	9
Tolland County	5
Hartford County	4
Windham County	3
Middlesex County	3
Fairfield County	2
New London County	1
Other localities	1

The complete county distribution, spread across 8 Connecticut counties. Every occurrence record falls in one county, so these sum to the total. Counties from GBIF and US Census boundaries.

Cinereus shrews, also called masked shrews, are among the smallest mammals in Connecticut, and their metabolism runs so fast they have to hunt insects and other invertebrates almost constantly to survive. Records cluster around the damp leaf litter and forest floor near Hammonasset, Bluff Point, and Barn Island, coastal woodland edges rather than the open marsh those refuges are best known for.

Records carry three bumps, May, June, and September, rather than one clean peak, likely tracking breeding and dispersal activity more than any single season of highest abundance, since this shrew stays active underground year-round rather than hibernating. NatureServe rates it secure (S5) in Connecticut, and with 37 records split fairly evenly between iNaturalist and GBIF, it’s one of the more consistently documented shrews in this rank range.

Occurrence data from iNaturalist and GBIF.

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 Connecticut 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
USGS Protected Areas Databasepublic domainthe named parks, forests, and refuges behind "notable places to look"