Aricia agestis
In 3 days ~30% in a week ~50%
Aricia agestis, the brown argus, is a butterfly in the family Lycaenidae. It is found throughout the Palearctic realm, north to northern Jutland (Denmark), west as far as coastal Wales and east to Siberia and the Tian Shan.
Above similar to the preceding,[ L. anteros ] deep dark brown, with strongly marked discocellular spot, especially in the male. Typical specimens have this spot black and bear red spots at the outer margin. Underside with numerous ocelli, the hindwing with a pale smear from the apex of the cell to the centre of the outer margin. From Scandinavia to the Sahara and northern India, and from the Canary Isles to... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Cévennes National Park | 🇫🇷 France | |
| 2 | Pyrénées National Park | 🇫🇷 France | |
| 3 | Fertő-Hanság National Park | 🇭🇺 Hungary | |
| 4 | Bavarian Forest National Park | 🇩🇪 Germany | |
| 5 | Wadden Sea National Park | 🇩🇪 Germany |
With luck
About 10% of wildlife watchers report a Brown Argus sighting in Rotterdam [The Hague] on a given day, based on 38 verified sightings from GBIF citizen-science data. It is the 62nd most-seen of the 355 insects we can rate there. Over three days the chance rises to about 30%, and over a week to about 50%, if each day is a fresh chance.
July
In that month about 20% of wildlife watchers report a Brown Argus in Rotterdam [The Hague] on a given day, against under 5% in November to March, the lowest months.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Brown Argus sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
5th of 20
Of the 20 cities where we can rate Brown Argus sightings, Rotterdam [The Hague] ranks 5th at about 10%. The best odds are in Jerusalem (Israel, about 20%), Budapest (Hungary, about 20%) and Ankara (Turkey, about 10%).
Same family: Lycaenidae
The closest relatives of the Brown Argus that you can see in Rotterdam [The Hague] (family Lycaenidae, Gossamer-winged Butterflies) are Common Blue (about 10%), Holly Blue (about 10%) and Small Copper (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Brown Argus is recorded against all the insects logged in Rotterdam [The Hague] (38 verified sightings), 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.
