Washington mammals

Silver-haired Bat in Washington

Lasionycteris noctivagans

Native to Washington S3 Vulnerable in Washington

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

IUCN Red List status

LC – Least Concern

Widespread and abundant; not at risk.

Photo: Mark Richman · CC BY 4.0Silver-haired bat tucked into loose barkPhoto: David LaMagna · CC BY 4.0Silver-haired bat roosting against barkPhoto: David LaMagna · CC BY 4.0Silver-frosted back of a silver-haired batPhoto: Jeff Bartlett · CC BY 4.0Live silver-haired bat perched on a rock face

Photo: Mark Richman · CC BY 4.0Silver-haired bat tucked into loose barkPhoto: David LaMagna · CC BY 4.0Silver-haired bat roosting against barkPhoto: David LaMagna · CC BY 4.0Silver-frosted back of a silver-haired batPhoto: Jeff Bartlett · CC BY 4.0Live silver-haired bat perched on a rock face

Silver-haired Bat in Washington, by the numbers

Occasional in Washington 74th most recorded of 145 mammals logged in Washington

167 occurrence records

59 with iNaturalist photos

Jun 18, 2026 Last seen in Washington

Records from 2000–2026.

167 total records count every Washington occurrence from GBIF and iNaturalist; the map plots a georeferenced sample of 166; the monthly chart covers the 166 records with a full observation date.

When to look for the Silver-haired Bat in Washington

Most sightings fall in September.

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

Monthly Washington records (table)

Month	Records
January	7
February	8
March	8
April	12
May	16
June	12
July	27
August	17
September	30
October	13
November	10
December	6

Monthly silver-haired bat occurrence records (iNaturalist and GBIF) in Washington, 2000–2026.

Seasonality

Year-round in Washington, with recorded sightings peaking in September, with a smaller rise in July.

Occurrence map

Where Silver-haired Bat has been recorded in Washington

166 records mapped · zoom and drag to explore

166 Washington records mapped

Notable places to look

Park, forest, or monument	iNaturalist records
San Juan Islands National Monument	3
Mount Rainier National Park	2
Washington State Department of Natural Resources (WADNR) State Resource Management Area	2
Wenaha-Tucannon Wilderness	2
Sacajawea	1
Glacier Peak Wilderness	1
Millersylvania Memorial	1
Daniel J. Evans Wilderness Area	1

Protected places with the most silver-haired 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 Washington

County	Records
King County	24
Pierce County	20
Walla Walla County	14
Whitman County	13
Spokane County	10
Columbia County	9
Snohomish County	7
Thurston County	7
Chelan County	6
Yakima County	5
Franklin County	4
Kitsap County	4
21 other counties	44

The complete county distribution, spread across 33 Washington counties. Every occurrence record falls in one county, so these sum to the total. Counties from GBIF and US Census boundaries.

Washington’s file for silver haired bat holds 167 records from 2000–2026. A feed comparison finds 59 iNaturalist records against 159 in GBIF, with duplicates reconciled in the combined figure. Measured strictly by submitted records, it sits 66 in the 126-species state list.

Reporting is most concentrated in September, with 30 records; December has only 6. A place-level count is available for Olympic National Park, which accounts for 1 record. The evidence measures when and where records entered the dataset, rather than biological abundance.

Occurrence data from iNaturalist and GBIF.

Full species profile Silver-haired Bat Lasionycteris noctivagans Size 9.5–11.5 cm3.7–4.5 in Weight 11 g0.4 oz Lifespan 12 yr View the full profile

More mammals in Washington 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"