Lycaeides idas
In 3 days ~40% in a week ~60%
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 Ecrins National Park on a given day, based on 17 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 70th most-seen of the 251 insects we can rate there. Over three days the chance rises to about 40%, and over a week to about 60%, if each day is a fresh chance.
July
In that month about 20% of wildlife watchers report a Northern Blue in Ecrins National Park on a given day, against under 5% in September–October and December–May, the lowest months. That is one of Ecrins National Park's driest months, with about 50 mm of rain against 160 mm in December.
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.
7th of 13
Of the 13 parks where we can rate Northern Blue sightings, Ecrins National Park ranks 7th 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 Ecrins National Park (family Lycaenidae, Gossamer-winged Butterflies) are Scarce Copper (about 30%), Chalkhill Blue (about 30%) and Damon Blue (about 30%), 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 Ecrins National Park (17 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.
