Wyoming mammals

American water shrew in Wyoming

Sorex palustris

Native to Wyoming

Not listed as nonindigenous in Wyoming by USGS NAS; treated as native to its mapped Wyoming 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.

American water shrew in Wyoming, by the numbers

Common in Wyoming 36th most recorded of 126 mammals logged in Wyoming

255 occurrence records

Records from 2000–2026.

When to look for the American water shrew in Wyoming

Most sightings fall in July to August.

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

Monthly Wyoming records (table)
MonthRecords
January1
February0
March0
April0
May3
June23
July109
August79
September25
October12
November2
December1

Monthly american water shrew occurrence records (iNaturalist and GBIF) in Wyoming, 2000–2026.

Seasonality

Year-round in Wyoming, with recorded sightings peaking in July–August.

Occurrence map

Where American water shrew has been recorded in Wyoming

255 records mapped · zoom and drag to explore

255 Wyoming records mapped

Notable places to look

Park, forest, or monumentiNaturalist records
Grand Teton National Park 9
Cloud Peak Wilderness 4
Teton Wilderness 4
Medicine Bow National Forest 3
Yellowstone National Park 2
Shoshone National Forest 1
University Landscaped 1
Teton National Forest 1

Protected places with the most american water 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 Wyoming

CountyRecords
Sheridan County 65
Albany County 65
Teton County 30
Carbon County 20
Park County 15
Lincoln County 15
Sublette County 11
Big Horn County 10
Uinta County 7
Natrona County 7
Fremont County 5
Converse County 4
Johnson County 1

The complete county distribution, spread across 13 Wyoming counties. Every occurrence record falls in one county, so these sum to the total. Counties from GBIF and US Census boundaries.

Wyoming has logged more water shrew records than nearly every other state that reports the species, second only to Utah, though nearly every one of the state’s 255 records comes from GBIF specimen and survey data rather than iNaturalist photos. That split makes sense for an animal that dives underwater to hunt by touch and rarely surfaces long enough for a camera.

Reports cluster tightly around cold mountain streams near Seedskadee National Wildlife Refuge, the National Elk Refuge, and the Yellowstone River corridor, the kind of clean, fast, well-oxygenated water this shrew needs to find the aquatic insect larvae it eats. Sightings peak sharply in July, when field surveys and stream access both pick up, not necessarily when the shrew itself is most active, since it hunts year-round beneath the water’s surface. With no formal state conservation rank on file, its status here is best read through that strong record count rather than any listing.

More mammals in Wyoming 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
  • 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"