Lycaeides idas
In 3 days ~20% in a week ~50%
Plebejus idas, the Idas blue or northern blue, is a butterfly of the family Lycaenidae. It belongs to the subfamily of Polyommatinae. This butterfly is very rare with low population densities. This mainly due to human disturbance effecting and creating changes in vegetation. According to the Nature Conservancy, it is critically endangered. It is ranked as Ti, critically imperiled (Zverev, 2021).
In the summer of 2014, a fire in Vastmanland in South Central Sweden affected an area of 13,100 ha. After the fire the Idas Blues along with other species increased in numbers. This is presumed to be because of an increase in larval host plant abundance.
This species can be found in most of Europe (except parts of Spain... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Kluane National Park | 🇨🇦 Canada | |
| 2 | Vanoise National Park | 🇫🇷 France | |
| 3 | Mercantour National Park | 🇫🇷 France | |
| 4 | Jasper National Park | 🇨🇦 Canada | |
| 5 | Banff National Park | 🇨🇦 Canada | |
| 6 | Sierra Nevada National Park | 🇪🇸 Spain | |
| 7 | Ecrins National Park | 🇫🇷 France | |
| 8 | Aigüestortes National Park | 🇪🇸 Spain | |
| 9 | Glacier National Park | 🇺🇸 United States | |
| 10 | Grand Teton National Park | 🇺🇸 United States | |
| 11 | Yellowstone National Park | 🇺🇸 United States | |
| 12 | Pyrénées National Park | 🇫🇷 France | |
| 13 | Wadden Sea National Park | 🇩🇪 Germany |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Munich | 🇩🇪 Germany |
With luck
About 10% of wildlife watchers report a Northern Blue sighting in Glacier National Park on a given day, based on 21 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 60th most-seen of the 147 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 50%, if each day is a fresh chance.
June to September
In those months about 10% of wildlife watchers report a Northern Blue in Glacier National Park on a given day, against under 5% in October to May, the lowest months.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Northern 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.
9th of 13
Of the 13 parks where we can rate Northern Blue sightings, Glacier National Park ranks 9th at about 10%. The best odds are in Kluane National Park (Canada, about 40%), Vanoise National Park (France, about 30%) and Mercantour National Park (France, about 30%). All parks ranked.
Same family: Lycaenidae
The closest relatives of the Northern Blue that you can see in Glacier National Park (family Lycaenidae, Gossamer-winged Butterflies) are Mariposa Copper (about 20%), Blue Copper (about 20%) and Arctic Blue (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Northern Blue is recorded against all the insects logged in Glacier National Park (21 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.
