Idaho mammals

Western Heather Vole in Idaho

Phenacomys intermedius

Native to Idaho S5 Secure in Idaho

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

Western heather vole tucked among moss and wet alpine leavesWestern heather vole moving away through moss and alpine ground cover
Photo: Aerin Jacob · CC BY 4.0Western heather vole tucked among moss and wet alpine leavesPhoto: Aerin Jacob · CC BY 4.0A western heather vole moving through mossy ground cover.

Western Heather Vole in Idaho, by the numbers

Occasional in Idaho 46th most recorded of 123 mammals logged in Idaho

109 occurrence records

Records from 2000–2026.

When to look for the Western Heather Vole in Idaho

Most sightings fall in July to August.

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

Monthly Idaho records (table)
MonthRecords
January0
February0
March0
April0
May0
June21
July39
August30
September19
October0
November0
December0

Monthly western heather vole occurrence records (iNaturalist and GBIF) in Idaho, 2000–2026.

Seasonality

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

Occurrence map

Where Western Heather Vole has been recorded in Idaho

109 records mapped · zoom and drag to explore

109 Idaho records mapped

Notable places to look

Park, forest, or monumentiNaturalist records
Kaniksu National Forest 38
Selway-Bitterroot Wilderness 9
Frank Church-River Of No Return Wilderness 4
Coeur d'Alene National Forest 3

Protected places with the most western heather vole 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 Idaho

CountyRecords
Bonner County 84
Idaho County 11
Lemhi County 5
Shoshone County 3
Custer County 2
Valley County 2
Boundary County 1
Blaine County 1

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

The Sawtooth National Recreation Area and the Frank Church and Selway-Bitterroot wilderness areas are exactly the kind of high, shrubby, subalpine country this vole favors, places where snowpack lingers and low ground cover survives largely undisturbed. Unlike most voles, which live on grass, this one browses bark, buds, and shrub leaves and caches food near its burrows for lean stretches.

All 109 Idaho records trace back to GBIF rather than iNaturalist, which fits a small, thick-furred rodent that field biologists usually confirm by skull and tooth features rather than a snapshot. Records run June through September with a July peak of 39, then drop to zero the rest of the year, though this species is known to stay active under snow through winter rather than truly disappear.

NatureServe ranks it S5, Secure, in Idaho, the top of the conservation scale, even with a record count this thin.

Western heather vole tucked among moss and wet alpine leaves
Full species profile Western Heather Vole Phenacomys intermedius Size 11.2 cm4.4 in Weight 40 g1.4 oz Lifespan 4 yr View the full profile

More mammals in Idaho 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"