Tortrix viridana
In 3 days ~20% in a week ~50%
The green oak tortrix, Tortrix viridana, also known as the European oak leafroller and the green oak moth, is a distinctive green moth whose larvae feed on tree leaves, especially oak. The head, forebody and front wings are green, the hind wings lightly greyish. The wingspan is 18-24 millimetres.
An infestation of the larvae can defoliate an oak tree. The adult female lays its eggs next to leaf buds, which the larvae consume when they emerge. As the larvae grow bigger they eat larger leaves, and then roll themselves up in a full-sized leaf to pupate.
Larvae occur from April to June; adults are on wing in June and July. The Ichneumon wasp Dirophanes invisor is a parasitoid which specializes on T. viridana. They are commonly found in many parts of Britain. In the Butterfly Conservation’s Microlepidoptera Report 2011 this species was classified as common. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Cévennes National Park | 🇫🇷 France | |
| 2 | Snowdonia National Park | 🇬🇧 United Kingdom | |
| 3 | Wadden Sea National Park | 🇩🇪 Germany | |
| 4 | Sierra de Guadarrama National Park | 🇪🇸 Spain |
With luck
About 10% of wildlife watchers report a Green Oak Tortrix sighting in Cévennes National Park on a given day, based on 21 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 329th most-seen of the 996 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.
June
In that month about 20% of wildlife watchers report a Green Oak Tortrix in Cévennes National Park on a given day, against under 5% in July to May, the lowest months.
Between 6 and 9 am
Across all the parks we cover, that three-hour window holds the most Green Oak Tortrix sightings with a recorded time, and about 7 in 10 of them come between 6 am and 6 pm: it is most active around dawn and dusk.
Yes
Of the 4 parks where we can rate Green Oak Tortrix sightings, Cévennes National Park has the highest daily chance: about 10%. Next come Snowdonia National Park (United Kingdom, about 10%) and Wadden Sea National Park (Germany, about 10%).
Same family: Tortricidae
The closest relatives of the Green Oak Tortrix that you can see in Cévennes National Park (family Tortricidae, Tortricid Leafroller Moths) are Privet Tortrix (about 10%), Codling Moth (about 10%) and Large Beech Piercer (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Green Oak Tortrix is recorded against all the insects logged in Cévennes National Park (21 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.
