Wyoming mammals

Townsend's Big-eared Bat in Wyoming

Corynorhinus townsendii

Native to Wyoming S2B,S1N Imperiled / Critically Imperiled in Wyoming

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

Townsend's big-eared bat roosting on a cave wallTownsend's big-eared bats tucked into a rock creviceCluster of hibernating Virginia big-eared bats on a cave ceilingVirginia big-eared bat hanging from a stone wallTownsend's big-eared bat roosting in a rocky crevice
Photo: Josh Weaver · CC BY 4.0Townsend's big-eared bat roosting on a cave wallPhoto: Brandon McCracken · CC BY 4.0Townsend's big-eared bats tucked into a rock crevicePhoto: Hajenga Jeff, U.S. Fish and Wildlife Service · Public domainCluster of hibernating Virginia big-eared bats on a cave ceilingPhoto: Stihler Craig, U.S. Fish and Wildlife Service · Public domainVirginia big-eared bat hanging from a stone wallPhoto: Pinnacles National Park · CC BY 4.0Townsend's big-eared bat roosting in a rocky crevice

Townsend's Big-eared Bat in Wyoming, by the numbers

Rare in Wyoming 100th most recorded of 126 mammals logged in Wyoming

36 occurrence records
8 with iNaturalist photos
Oct 2, 2025 Last seen in Wyoming

Records from 2000–2026.

When to look for the Townsend's Big-eared Bat in Wyoming

Most sightings fall in July to September.

36 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
February1
March0
April4
May3
June1
July5
August7
September6
October4
November2
December2

Monthly townsend's big-eared bat occurrence records (iNaturalist and GBIF) in Wyoming, 2000–2026.

Seasonality

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

Occurrence map

Where Townsend's Big-eared Bat has been recorded in Wyoming

36 records mapped · zoom and drag to explore

36 Wyoming records mapped

Notable places to look

Park, forest, or monumentiNaturalist records
Medicine Bow National Forest 2
Jedediah Smith Wilderness 1
Fort Laramie National Historic Site 1

Protected places with the most townsend's big-eared bat 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
Platte County 11
Goshen County 6
Weston County 3
Converse County 3
Carbon County 2
Hot Springs County 2
Natrona County 2
Albany County 2
Teton County 1
Sweetwater County 1
Big Horn County 1
Fremont County 1
Crook 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.

Townsend’s big-eared bat is named for ears that can rival its body length, folded back against the head at rest and raised to hunt moths by sound alone. Its 36 Wyoming records cluster around the Red Desert and Seedskadee National Wildlife Refuge, with a fairly even iNaturalist-GBIF split (8 to 33) suggesting both cave-survey work and occasional direct sightings near roost sites.

NatureServe splits its Wyoming rank by season, S2B (Imperiled) for the breeding population and S1N (Critically Imperiled) for wintering bats, reflecting how few hibernation caves and mines the species uses statewide. Records spread fairly evenly across the year with no single dominant peak, consistent with a species tied more to specific roost sites than to a broad seasonal migration.

Occurrence data from iNaturalist and GBIF.

Townsend's big-eared bat roosting on a cave wall
Full species profile Townsend's Big-eared Bat Corynorhinus townsendii Size 5.8 cm2.3 in Weight 9–11 g0.3–0.4 oz Lifespan 16 yr View the full profile

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
  • 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"