Cameraria ohridella
In 3 days ~20% in a week ~50%
The horse-chestnut leaf miner (Cameraria ohridella) is a leaf-mining moth of the family Gracillariidae. The horse-chestnut leaf miner was first observed in North Macedonia in 1984, and was described as a new species in 1986. Its larvae are leaf miners on the common horse-chestnut (Aesculus hippocastanum). The horse-chestnut leafminer was first collected and inadvertently pressed in herbarium sheets by the botanist Theodor von Heldreich in central Greece in 1879.
Cameraria ohridella causes significant damage, mainly late summer browning, to the appearance of horse-chestnut trees. Despite the poor appearance of these infested trees, there is no evidence that damage by the moth leads to tree death. Seed weight, photosynthetic storage and reproductive capacity may however be reduced. Trees survive repeated infestations and re-flush normally in the following year. It appears that most of the damage caused by the moth occurs too late in the growing season to greatly affect tree performance. Consequently, there is no reason to fell and remove trees just because they are attacked by C. ohridella.
The larva feeds in a mine in the leaves of the tree, damaging the leaves and stunting... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Triglav National Park | 🇸🇮 Slovenia | |
| 2 | Snowdonia National Park | 🇬🇧 United Kingdom | |
| 3 | Bavarian Forest National Park | 🇩🇪 Germany | |
| 4 | Wadden Sea National Park | 🇩🇪 Germany |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Liverpool | 🇬🇧 United Kingdom | |
| 2 | Kyiv | 🇺🇦 Ukraine | |
| 3 | Kharkiv | 🇺🇦 Ukraine | |
| 4 | London | 🇬🇧 United Kingdom | |
| 5 | Minsk | 🇧🇾 Belarus | |
| 6 | Sofia | 🇧🇬 Bulgaria | |
| 7 | Berlin | 🇩🇪 Germany | |
| 8 | Manchester | 🇬🇧 United Kingdom | |
| 9 | Warsaw | 🇵🇱 Poland | |
| 10 | Birmingham | 🇬🇧 United Kingdom |
With luck
About 10% of wildlife watchers report a Horse-Chestnut Leafminer sighting in Triglav National Park on a given day, based on 6 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 212th most-seen of the 260 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 to September
In those months about 10% of wildlife watchers report a Horse-Chestnut Leafminer in Triglav National Park on a given day, against under 5% in October to May, the lowest months.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Horse-Chestnut Leafminer sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Yes
Of the 4 parks where we can rate Horse-Chestnut Leafminer sightings, Triglav National Park has the highest daily chance: about 10%. Next come Snowdonia National Park (United Kingdom, about 10%) and Bavarian Forest National Park (Germany, about 10%).
Same order: Lepidoptera
The closest relatives of the Horse-Chestnut Leafminer that you can see in Triglav National Park (order Lepidoptera, Butterflies and Moths) are Silver-Washed Fritillary (about 60%), Marbled White (about 40%) and Nine-Spotted Moth (about 40%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Horse-Chestnut Leafminer is recorded against all the insects logged in Triglav National Park (6 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.
