Nevada mammals

Big Brown Bat in Nevada

Eptesicus fuscus

Native to Nevada S3 Vulnerable in Nevada

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

Big Brown Bats (Eptesicus fuscus)Big brown bat flying in daylight with wings spreadBig brown bat flying at night with wings spreadBig brown bat roosting on lichen-covered tree barkBig brown bat roosting on a wooden structure
Photo: Connor Long · CC BY-SA 4.0Big Brown Bats (Eptesicus fuscus)Photo: rhododendrites · CC-BY-SABig brown bat flying in daylight with wings spreadPhoto: Dan Riskin · CC-BYBig brown bat flying at night with wings spreadPhoto: Rita Clare · CC0Big brown bat roosting on lichen-covered tree barkPhoto: Bonnie Isaac · CC0Big brown bat roosting on a wooden structure

Big Brown Bat in Nevada, by the numbers

Occasional in Nevada 75th most recorded of 142 mammals logged in Nevada

27 occurrence records
22 with iNaturalist photos
Aug 18, 2024 Last seen in Nevada

Records from 2000–2026.

27 total records count every Nevada occurrence from GBIF and iNaturalist; the map plots a georeferenced sample of 26; the monthly chart covers the 26 records with a full observation date.

When to look for the Big Brown Bat in Nevada

Most sightings fall in May.

26 Nevada occurrence records (iNaturalist and GBIF) by month of year, 2000–2026. Shows when the species is recorded, not a guarantee of presence. Based on a small number of dated records; the seasonal pattern may not be representative.

Monthly Nevada records (table)
MonthRecords
January0
February0
March0
April4
May8
June2
July4
August8
September0
October0
November0
December0

Monthly big brown bat occurrence records (iNaturalist and GBIF) in Nevada, 2000–2026.

Seasonality

Year-round in Nevada, with recorded sightings peaking in May, with a smaller rise in August.

Occurrence map

Where Big Brown Bat has been recorded in Nevada

26 records mapped · zoom and drag to explore

26 Nevada records mapped

Notable places to look

Park, forest, or monumentiNaturalist records
Toiyabe National Forest 3
Great Basin National Park 1
Gold Butte National Monument 1

Protected places with the most big brown 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 Nevada

CountyRecords
Clark County 8
Nye County 7
Washoe County 4
Lyon County 2
White Pine County 2
Eureka County 1
Douglas County 1
Elko County 1
Other localities 1

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

Great Basin National Park and Humboldt-Toiyabe National Forest provide the clearest named anchors for Nevada’s big brown bat records, placing documented encounters along the state’s mountain spine.

These sites tie the Nevada record pattern to the state’s long mountain spine. Records from separate ranges matter because Nevada’s high country is broken into isolated peaks. The strongest reporting falls in summer, when Nevada’s high country is easiest to reach but low deserts are hottest. That may shape where observers submit records.

The source fields contain 22 research-grade iNaturalist records and 20 GBIF records; after the sources are combined, the overlay reports 27 Nevada records. Source overlap means those inputs should not be added as an abundance figure. The species is native to Nevada, has no specific state listing here, and is listed as Least Concern by the IUCN.

Occurrence data from iNaturalist and GBIF.

Big Brown Bats (Eptesicus fuscus)
Full species profile Big Brown Bat Eptesicus fuscus Size 7.5 cm3 in Weight 17 g0.6 oz Lifespan 19 yr View the full profile

More mammals in Nevada 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"