Callophrys polios
In 3 days ~20% in a week ~40%
Callophrys polios, the hoary elfin, is a butterfly of the family Lycaenidae. It is listed as a species of special concern and believed extirpated in the US state of Connecticut. The wingspan is 22–29 mm. Adults are on wing from April to June in one generation.
The larvae feed on Arctostaphylos uva-ursi and possibly Epigaea repens. The adults feed on flower nectar from various species, including leatherleaf, pyxie, wild strawberry and willow. Hibernation takes place as a chrysalid. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Isle Royale National Park | 🇺🇸 United States | |
| 2 | Rocky Mountain National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Calgary | 🇨🇦 Canada |
With luck
About 10% of wildlife watchers report a Hoary Elfin sighting in Rocky Mountain National Park on a given day, based on 19 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 97th 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.
May
In that month about 20% of wildlife watchers report a Hoary Elfin in Rocky Mountain National Park on a given day, against under 5% in July to March, the lowest months.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Hoary Elfin sightings with a recorded time, and nearly all of them come between 6 am and 6 pm: it is a daytime animal.
2nd of 2
Of the 2 parks where we can rate Hoary Elfin sightings, Rocky Mountain National Park ranks 2nd at about 10%. The best odds are in Isle Royale National Park (United States, about 20%).
GBIF citizen-science records
It is estimated from how often the Hoary Elfin is recorded against all the insects logged in Rocky Mountain National Park (19 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.
