Best Time to See Bats in Oregon
August, July and September is the best time to see bats in Oregon. Based on 1,013 verified iNaturalist observations, here is exactly when bats are most active across the year in Oregon.
By Tim, founder of Easy Street Markets. I maintain the wildlife database and verify every animal and source myself. Updated July 2, 2026.
Townsend's Big-eared Bat · Michele Wiseman CC BY
Little Brown Bat · Public domain CC0
Mexican Free-tailed Bat · Hilary Rose Dawson CC BY
1,013 verified observations of bats in Oregon, recorded across 12 months of the year on iNaturalist.
When bats are recorded in Oregon
Peak month
August
220 records (21.7% of the year)
| Month | Observations | Share |
|---|---|---|
| January | 20 | 2% |
| February | 28 | 2.8% |
| March | 44 | 4.3% |
| April | 53 | 5.2% |
| May | 119 | 11.7% |
| June | 130 | 12.8% |
| Julypeak | 164 | 16.2% |
| Augustpeak | 220 | 21.7% |
| Septemberpeak | 152 | 15% |
| October | 51 | 5% |
| November | 17 | 1.7% |
| December | 15 | 1.5% |
Bats you are most likely to see
| Species | Verified observations |
|---|---|
| Big Brown Bat | 109 |
| Little Brown Bat | 103 |
| Townsend's Big-eared Bat | 81 |
| Silver-haired Bat | 47 |
| California Myotis | 35 |
| Long-eared Myotis | 31 |
| Northern Hoary Bat | 23 |
| Yuma Myotis | 13 |
Weather to expect, source Open-Meteo
Typical weather in Oregon
Recent typical conditions by month, so you can plan a trip around both when bats are active and what the weather is doing. The best months to look for bats sit around 47 to 83 degrees Fahrenheit, so pack for that.
| Month | Avg high | Avg low | Rain |
|---|---|---|---|
| Jan | 39°F | 26°F | 2" |
| Feb | 38°F | 22°F | 2.4" |
| Mar | 43°F | 25°F | 1.9" |
| Apr | 52°F | 32°F | 2.2" |
| May | 61°F | 40°F | 2" |
| Jun | 71°F | 48°F | 1.1" |
| Julbest time | 83°F | 56°F | 0.1" |
| Augbest time | 81°F | 56°F | 0.4" |
| Sepbest time | 71°F | 47°F | 1.2" |
| Oct | 58°F | 37°F | 1.2" |
| Nov | 45°F | 28°F | 2.3" |
| Dec | 37°F | 25°F | 2.4" |
Typical recent conditions (5-year means) from the Open-Meteo archive, averaged for Oregon. Weather varies year to year, so treat these as a guide.
More on bats in Oregon:
Sightings of bats in Oregon peak in August, when 220 of the year's 1,013 verified observations are logged — about 21.7% of the annual total. Activity stays high through August, July and September.
The quietest stretch is December, November and January, when bats are hardest to find — December sees just 15 records. If a reliable sighting matters, plan around the peak window rather than the off-season.
The bats you are most likely to encounter in Oregon are Big Brown Bat, Little Brown Bat and Townsend's Big-eared Bat — the most-recorded species in the state. Each keeps its own seasonal rhythm, but the month-by-month pattern above reflects every reported sighting together.
Where to go
Best places to see bats in Oregon
- Crater Lake National Park — National Park
- Fort Vancouver National Historic Site — National Historic Site
- Lewis & Clark National Historic Trail — National Historic Trail
- Lewis and Clark National Historical Park — National Historical Park
- Nez Perce National Historical Park — National Historical Park
- Oregon Caves National Monument & Preserve — National Monument & Preserve
Gear to see them
Frequently asked questions
What is the best month to see bats in Oregon?+
August is the single best month, and the broader peak window runs through August, July and September, based on 1,013 verified iNaturalist observations.
When are bats hardest to see in Oregon?+
December is the quietest month for bats in Oregon, with only 15 verified records.
Are bats active year-round in Oregon?+
Bats are recorded in 12 of 12 months in Oregon, so they can be seen year-round, with a clear peak in August.