Lycaeides idas
In 3 days ~70% in a week ~90%
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 |
Possible
About 30% of wildlife watchers report a Northern Blue sighting in Vanoise National Park on a given day, based on 59 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 18th most-seen of the 308 insects we can rate there. Over three days the chance rises to about 70%, and over a week to about 90%, if each day is a fresh chance.
July and August
In those months about 40% of wildlife watchers report a Northern Blue in Vanoise National Park on a given day, against under 5% in September–October and December–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.
2nd of 13
Of the 13 parks where we can rate Northern Blue sightings, Vanoise National Park ranks 2nd at about 30%. The best odds are in Kluane National Park (Canada, about 40%). All parks ranked.
Same family: Lycaenidae
The closest relatives of the Northern Blue that you can see in Vanoise National Park (family Lycaenidae, Gossamer-winged Butterflies) are Scarce Copper (about 40%), Damon Blue (about 40%) and Chalkhill Blue (about 40%), 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 Vanoise National Park (59 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.
