Icaricia saepiolus
In 3 days ~20% in a week ~40%
Plebejus saepiolus, formerly Icaricia saepiolus, the greenish blue, is a butterfly of the family Lycaenidae. It is found from the northwestern United States to southern Saskatchewan and Alberta. The wingspan is 21–28 mm. Adults are on wing from June to August.
The larvae feed on Trifolium monathum, Trifolium longipes, and Trifolium wormskioldii. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Kluane National Park | 🇨🇦 Canada | |
| 2 | Elk Island National Park | 🇨🇦 Canada | |
| 3 | Yosemite National Park | 🇺🇸 United States | |
| 4 | Jasper National Park | 🇨🇦 Canada | |
| 5 | Rocky Mountain National Park | 🇺🇸 United States | |
| 6 | Banff National Park | 🇨🇦 Canada | |
| 7 | Sequoia and Kings Canyon National Parks | 🇺🇸 United States | |
| 8 | Olympic National Park | 🇺🇸 United States | |
| 9 | Riding Mountain National Park | 🇨🇦 Canada | |
| 10 | Yellowstone National Park | 🇺🇸 United States | |
| 11 | Grand Teton National Park | 🇺🇸 United States | |
| 12 | Glacier National Park | 🇺🇸 United States | |
| 13 | Grand Canyon National Park | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Greenish Blue sighting in Yellowstone National Park on a given day, based on 16 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 62nd most-seen of the 160 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 Greenish Blue in Yellowstone 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 Greenish Blue sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
10th of 13
Of the 13 parks where we can rate Greenish Blue sightings, Yellowstone National Park ranks 10th at about 10%. The best odds are in Kluane National Park (Canada, about 40%), Elk Island National Park (Canada, about 20%) and Yosemite National Park (United States, about 20%).
Same genus: Icaricia
The closest relatives of the Greenish Blue that you can see in Yellowstone National Park (genus Icaricia) are Boisduval's Blue (about 10%) and Lupine Blue (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Greenish Blue is recorded against all the insects logged in Yellowstone National Park (16 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.
