Andricus quercuscalicis
In 3 days ~20% in a week ~50%
Andricus quercuscalicis is a gall wasp species inducing knopper galls. Knopper galls develop as a chemically induced distortion of growing acorns on pedunculate oak (Quercus robur L.) trees, caused by gall wasps, which lay eggs in buds with their ovipositor. The gall thus produced can greatly reduce the fecundity of the oak host, making this gall potentially more of a threat to the reproductive ability of the tree than those that develop on leaves, buds, stems, etc.
The large 2 cm gall growth appears as a mass of green to yellowish-green, ridged, and at first sticky plant tissue on the bud of the oak, that breaks out as the gall between the cup and the acorn. If only a few grubs are developing within, then it may appear only as a group of bland folds. Where several grubs are competing for space the shape may become much more contorted, with several tightly bunched galls.
The word knopper derives from the German word 'Knoppe', meaning a kind of felt cap or helmet worn during the 17th century; also a small rounded protuberance, often decorative, such as a stud, a tassel or a knob. Although normally distinctive the knopper gall can, under some... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Liverpool | 🇬🇧 United Kingdom | |
| 2 | London | 🇬🇧 United Kingdom | |
| 3 | Manchester | 🇬🇧 United Kingdom | |
| 4 | Birmingham | 🇬🇧 United Kingdom | |
| 5 | Budapest | 🇭🇺 Hungary | |
| 6 | Dublin | 🇮🇪 Ireland | |
| 7 | Copenhagen | 🇩🇰 Denmark | |
| 8 | Vienna | 🇦🇹 Austria | |
| 9 | Leeds | 🇬🇧 United Kingdom | |
| 10 | Bucharest | 🇷🇴 Romania |
With luck
About 10% of wildlife watchers report a Knopper Gall Wasp sighting in Dublin on a given day, based on 18 verified sightings from GBIF citizen-science data. It is the 43rd most-seen of the 121 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 50%, if each day is a fresh chance.
August
In that month about 30% of wildlife watchers report a Knopper Gall Wasp in Dublin on a given day, against under 5% in September and November–June, the lowest months.
6th of 19
Of the 19 cities where we can rate Knopper Gall Wasp sightings, Dublin ranks 6th at about 10%. The best odds are in Liverpool (United Kingdom, about 20%), London (United Kingdom, about 20%) and Manchester (United Kingdom, about 20%).
GBIF citizen-science records
It is estimated from how often the Knopper Gall Wasp is recorded against all the insects logged in Dublin (18 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.
