Iowa mammals

Northern Short-tailed Shrew in Iowa

Blarina brevicauda

Native to Iowa S5 Secure in Iowa

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

Northern Short-tailed Shrew in Iowa, by the numbers

Common in Iowa 18th most recorded of 74 mammals logged in Iowa

619 occurrence records
106 with iNaturalist photos
May 11, 2026 Last seen in Iowa

619 total records count every Iowa occurrence from GBIF and iNaturalist; the map plots a georeferenced sample of 300; the monthly chart covers the 613 records with a full observation date.

When to look for the Northern Short-tailed Shrew in Iowa

Most sightings fall in August.

613 Iowa occurrence records (iNaturalist and GBIF) by month of year. Shows when the species is recorded, not a guarantee of presence.

Monthly Iowa records (table)
MonthRecords
January5
February7
March10
April12
May71
June35
July77
August161
September53
October115
November40
December27

Monthly northern short-tailed shrew occurrence records (iNaturalist and GBIF) in Iowa.

Seasonality

Year-round in Iowa, with recorded sightings peaking in August, with a smaller rise in October.

Occurrence map

Where Northern Short-tailed Shrew has been recorded in Iowa

300 records mapped · zoom and drag to explore

300 Iowa records mapped

Notable places to look

Park, forest, or monumentiNaturalist records
Effigy Mounds National Monument 5
Decorah and the Driftless Area 3
Iowa Lakeside Lab 3
Loess Hill Wildlife Management Area 3
Saylorville Wildlife Management Area 3
Cayler Prairie State Preserve 3
Maquoketa Caves State Park 2
Springbrook State Park 2

Protected places with the most northern short-tailed 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 Iowa

CountyRecords
Fremont County 41
Taylor County 38
Marion County 31
Winneshiek County 29
Page County 27
Mills County 27
Story County 26
Montgomery County 25
Johnson County 23
Grundy County 21
Linn County 18
Hardin County 18
63 other counties 295

The complete county distribution, spread across 75 Iowa counties. Every occurrence record falls in one county, so these sum to the total. Counties from GBIF and US Census boundaries.

Iowa’s occurrence databases hold 619 northern short-tailed shrew records, and the overwhelming majority come from GBIF specimen data rather than casual sightings, a strong sign this is an animal most people in Iowa never actually see, even where it’s frequently recorded.

Karst country and leaf litter, not open prairie

This shrew burrows through loose, moist soil and leaf litter hunting earthworms, insects, and snails, and it needs exactly the kind of ground the Driftless Area and Maquoketa Caves State Park provide: limestone karst riddled with sinkholes and cave passages, under a cover of hardwood leaf litter that stays damp and diggable through most of the year. Iowa’s restored tallgrass prairie, like the plantings at Neal Smith National Wildlife Refuge, offers thinner cover and fewer invertebrates below ground, so shrews there likely cluster along wooded edges and ravines rather than the open grass.

What the record spike really tracks

Records jump sharply in August and October and stay scarce from January through April, but that swing says more about when Iowa’s small-mammal surveys run than about the shrew’s own activity. The species doesn’t hibernate. It stays active under snow and leaf litter all winter, burning through an unusually high metabolism that forces it to hunt nearly nonstop just to survive the cold.

Status in Iowa

NatureServe ranks the northern short-tailed shrew S5, secure, and native to Iowa. It’s one of the most physiologically demanding small mammals in the state, a venomous hunter that has to keep eating through every season just to stay alive.

Occurrence data from iNaturalist and GBIF.

More mammals in Iowa in the atlas

Data & sources

The data and visualizations on this page draw on these open sources: