Erebia epipsodea
In 3 days ~20% in a week ~40%
Erebia epipsodea, the common alpine, is a butterfly species of the subfamily Satyrinae of family Nymphalidae. It is found in North America from Alaska south through the Rocky Mountains to northern New Mexico and east across the prairie provinces to southwest Manitoba.
The wingspan is 34–45 mm (1.3–1.8 in). Adults are on wing from mid-June to early August. The larvae feed on various grass species. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Elk Island National Park | 🇨🇦 Canada | |
| 2 | Yellowstone National Park | 🇺🇸 United States | |
| 3 | Jasper National Park | 🇨🇦 Canada | |
| 4 | Banff National Park | 🇨🇦 Canada | |
| 5 | Riding Mountain National Park | 🇨🇦 Canada | |
| 6 | Grand Teton National Park | 🇺🇸 United States | |
| 7 | Glacier National Park | 🇺🇸 United States | |
| 8 | Rocky Mountain National Park | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Common Alpine sighting in Rocky Mountain National Park on a given day, based on 20 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 72nd most-seen of the 191 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 40%, if each day is a fresh chance.
June and July
In those months about 10% of wildlife watchers report a Common Alpine in Rocky Mountain National Park on a given day, against under 5% in August to May, the lowest months.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Common Alpine sightings with a recorded time, and nearly all of them come between 6 am and 6 pm: it is a daytime animal.
8th of 8
Of the 8 parks where we can rate Common Alpine sightings, Rocky Mountain National Park ranks 8th at about 10%. The best odds are in Elk Island National Park (Canada, about 20%), Yellowstone National Park (United States, about 10%) and Jasper National Park (Canada, about 10%).
GBIF citizen-science records
It is estimated from how often the Common Alpine is recorded against all the insects logged in Rocky Mountain National Park (20 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
