Tephritis bardanae
In 3 days ~20% in a week ~40%
Tephritis bardanae is a picture-winged fly of the family Tephritidae, which are variously known as fruit-flies (North America) or gall flies (Britain and Ireland). The larvae feed in the flower-heads (capitula) of species of Arctium (burdocks), causing galls to form.
The larvae pupates in autumn, forming a black puparium. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Helsinki | 🇫🇮 Finland | |
| 2 | Stockholm | 🇸🇪 Sweden | |
| 3 | Brussels | 🇧🇪 Belgium | |
| 4 | Rotterdam [The Hague] | 🇳🇱 Netherlands | |
| 5 | Kazan | 🇷🇺 Russia | |
| 6 | Yekaterinburg | 🇷🇺 Russia | |
| 7 | London | 🇬🇧 United Kingdom | |
| 8 | Saint Petersburg | 🇷🇺 Russia | |
| 9 | Moscow | 🇷🇺 Russia |
With luck
About 10% of wildlife watchers report a Burdock Fly sighting in Helsinki on a given day, based on 42 verified sightings from GBIF citizen-science data. It is the 163rd most-seen of the 838 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 40%, if each day is a fresh chance.
June–July and November
In those months about 10% of wildlife watchers report a Burdock Fly in Helsinki on a given day, against under 5% in August–October and December–May, the lowest months.
Yes
Of the 9 cities where we can rate Burdock Fly sightings, Helsinki has the highest daily chance: about 10%. Next come Stockholm (Sweden, about 10%) and Brussels (Belgium, about 10%).
GBIF citizen-science records
It is estimated from how often the Burdock Fly is recorded against all the insects logged in Helsinki (42 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.
