Boloria dia
In 3 days ~30% in a week ~50%
Boloria dia, the Weaver's fritillary or violet fritillary, is a butterfly in the family Nymphalidae. The name Weaver's fritillary is in honor of Richard Weaver, an English insect collector who claimed to have obtained the specimen within ten miles of Birmingham around 1820. However, B. dia is very rare in England and the few specimens known from there are thought to be from possibly accidental introductions.
The adult is a small fritillary with typically chequered orange-brown upperside and a submarginal row of triangles and dots. The forewing is 16–17 mm long. The underside of the hindwing has a distinctive purplish band. A. dia L. (68f) is the smallest Argynnis. Above usually more extended black than the other species; the basal area of the hindwing as a rule quite dark, the marginal area with a row of heavy black dots. The hindwing beneath variegated with purple and bearing silvery spots at the margin, in the median band and at the base.
Throughout Central, North and East Europe, also in Anterior Asia eastwards to Mongolia. Specimens with a broad confluent median band are ab. vittata Spul. (= mediofasciata Schultz). In ab. hudaki Aign... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Picos de Europa National Park | 🇪🇸 Spain | |
| 2 | Aigüestortes National Park | 🇪🇸 Spain | |
| 3 | Pyrénées National Park | 🇫🇷 France | |
| 4 | Cévennes National Park | 🇫🇷 France | |
| 5 | Ecrins National Park | 🇫🇷 France | |
| 6 | Triglav National Park | 🇸🇮 Slovenia | |
| 7 | Mercantour National Park | 🇫🇷 France | |
| 8 | Bavarian Forest National Park | 🇩🇪 Germany |
With luck
About 10% of wildlife watchers report a Weaver's Fritillary sighting in Ecrins National Park on a given day, based on 11 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 119th most-seen of the 251 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.
May and September
In those months about 20% of wildlife watchers report a Weaver's Fritillary in Ecrins National Park on a given day, against under 5% in June and October–April, the lowest months.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Weaver's Fritillary 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 8
Of the 8 parks where we can rate Weaver's Fritillary sightings, Ecrins National Park ranks 5th at about 10%. The best odds are in Picos de Europa National Park (Spain, about 20%), Aigüestortes National Park (Spain, about 20%) and Pyrénées National Park (France, about 20%).
GBIF citizen-science records
It is estimated from how often the Weaver's Fritillary is recorded against all the insects logged in Ecrins National Park (11 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.
